Isospeed Cream Review: The Softest Poly, or Just Marketing?

Isospeed Cream arrives with one of the boldest promises in the poly aisle: a string marketed as possibly the softest co-polyester you can put in a racquet, with the tension maintenance of a proper control poly. That is a big claim, and I came to this string genuinely curious rather than sold. Isospeed is an Austrian brand — made by Isosport in Eisenstadt, a synthetics manufacturer that has been producing tennis strings since 1990 — and it has spent years chasing arm-friendly polyester, with Cream meant to be the payoff. I strung it, hit with it across a couple of frames, handed it to my partner, and came away with a more complicated verdict than the marketing suggests. Here is what actually happened on court with it, and who I think it is really for.

Isospeed Cream specs: construction, shape and gauges

Before opinions, the facts. Cream is a co-polyester monofilament with a round cross-section, which already tells you a lot about how it wants to play — round polys are control-first and spin-second compared with the sharp shaped strings that dominate the spin conversation. What makes Cream unusual is the recipe: Isospeed blends polyester with an elastomer to raise elasticity, rather than leaning on polyester alone. It comes in two gauges, 1.23mm (17) and 1.28mm (16L), both in a cream/off-white colour, finished with the brand's Liquid Wax coating for a lower-friction surface and cleaner snapback.

Isospeed also stacks its usual technology list here — Pre-Stretched, Double Heating, Spring Load and that Liquid Wax coat — all aimed at minimising tension loss. Independent playtesting backs the tension-maintenance story up: Cream reads as a soft-for-poly string with genuinely good tension retention. You can see the full spec breakdown on the Isospeed Cream product page, where it currently sits at $24.00 AUD per set. Where independent, long-form reviews of Cream are thin for a boutique poly, I have leaned on manufacturer specs plus the genuine coverage that exists, and I will flag where playtesters disagree.

Isospeed Cream tension: where it comes alive

Tennisnerd hammers this point and I agree with it completely — tension matters more than any racquet spec, and with Isospeed Cream it is the difference between the string the box promises and the string some people actually get. Isospeed Cream is a low-powered co-poly. String it like a normal control poly in the mid-50s and you are asking a soft string to behave like a firm one, and the "softest poly ever" magic largely disappears.

My advice: string it low. I settled in the mid-40s (lbs), roughly 10% under where you would put a synthetic gut or multi, and that is where the string finally breathed. Lower tension is what unlocks the pocketing, the comfort and enough depth to keep a low-powered poly from feeling dead. Push it up toward the mid-50s and Cream gets crisp and precise but also firmer and less forgiving — which matters, because the whole reason to buy Cream is comfort. If you string it high you are paying for a feature you then switch off. Start low, and only climb if you are spraying the ball long.

How Isospeed Cream plays: feel, control and comfort

I take the ball early and on the rise — an aggressive baseliner who wants depth, pace and placement over big loopy topspin. Short dwell time means firm, round control polys rarely feel jarring to me, so on paper Cream and my game should get along. Strung low in a control-friendly frame, they mostly did.

Isospeed Cream in a dense-pattern control frame

My best sessions with Cream came in the Tecnifibre TFight 305S (98, 18x19, RA 64) at 45 lbs. The dense 18x19 pattern is exactly the environment this string wants. Player consensus and my own on-court experience point the same way: Cream is happiest in a tighter pattern where the mains sit close and stay put. The connected, communicative feel I look for was there, control on flatter drives was genuinely good, and the response stayed comfortable through long baseline rallies. For a control poly, the ball stayed low off my racquet — which suits taking it early, because I am not fighting a high launch angle that leaves the ball sitting up.

Isospeed Cream in a low-RA all-rounder

I also ran Cream in the Head Gravity Tour (98, 16x19, RA 59). The low stiffness of that frame is forgiving enough that Cream never felt harsh, and the extra pocketing at 45 lbs gave me a touch more depth. Spin was fine — respectable rather than a defining feature, which is what you should expect from a round poly. If you want a shaped-spin monster, Cream is the wrong string; go look at a Solinco Tour Bite. If you want a round control poly that treats your arm well, Cream makes more sense.

Isospeed Cream comfort: is it really the softest poly?

This is where I have to be honest, because the comfort story around Cream is not unanimous. Tennis Warehouse's playtest team rated it one of the softest co-polys they had ever hit and an obvious pick for big hitters tired of trading comfort for control. That matches the marketing. But Tennisnerd's reviewer came away disappointed, describing a "concrete polyester feel" in an open-pattern frame strung in the mid-50s, with more string movement than expected — closer to a firm poly than the pillowy comfort string on the label.

Both experiences are real, and the gap between them is the whole point. Cream is soft for a poly, but it is still a poly, and it rewards being set up correctly. Strung low in a control-oriented pattern, I found it comfortable and easy on the elbow. Strung tight in an open pattern, it can read firm and move around. If arm health is your reason for shopping, that setup sensitivity matters — and it is why I would not put Cream in the same "safest of the safe" bracket as a true multifilament. For where it sits among gentler options, our guide to the most arm-friendly tennis strings of 2026 is a useful reality check.

Isospeed Cream durability and string movement

Two candid caveats. First, durability. Cream is not a string for chronic breakers — playtesters have reported the crosses filing down to a thin filament and snapping, and Tennisnerd's tester broke his after a handful of hours on a mishit. If you saw through poly in a week, Cream will not change your life. Second, string movement: in more open patterns the mains can wander and want nudging back between points. Neither is a dealbreaker for the right player, but both are real, and pretending otherwise would not help you.

The flip side is the tension maintenance, which genuinely is a strength. Cream held its tension well across my sessions, so the playability window stayed open longer than the raw comfort would suggest. You are more likely to cut Cream out because it moved or shredded than because it went dead — an unusual profile for a poly.

Who Isospeed Cream is for

I handed a set to my partner, who plays a Head Extreme MP L (100, 16x19, ~280g) at around 52 lbs with a much more topspin-driven, open-pattern game. It is a fair test of the arm-friendly pitch on a lower swing speed — and it also exposed exactly what the reviews warn about. In that open 16x19 pattern the string moved more, and the low-powered response asked her to supply pace she does not always have on hand. The comfort was there, but the fit was not ideal; her spin-hungry game is better served by her current Solinco Tour Bite.

So who should buy Isospeed Cream? Comfort-seeking control players with reasonable racquet-head speed, ideally in denser patterns, who want a round poly that is kinder to the arm than a Luxilon Alu Power or a Babolat RPM Blast without going full multifilament. Big flat hitters who over-hit with livelier strings will appreciate the low power. If you break strings fast, chase maximum shaped spin, or want a genuinely plush arm-saver with zero setup fuss, look elsewhere. Set up thoughtfully — strung low, in the right frame — Isospeed Cream is a likeable, honest control poly with a comfort streak. Available now at The Tennis Store with shipping across Australia.

Isospeed Cream FAQ

What tension should I string Isospeed Cream at?

String it low — I liked the mid-40s (lbs), around 10% below where you would put a synthetic gut or multifilament. Isospeed Cream is a low-powered control poly, and lower tension is what unlocks its pocketing and comfort. Higher tensions in the mid-50s add crispness and control but make it feel firmer, which works against its main selling point.

What gauge does Isospeed Cream come in?

Two gauges: 1.23mm (17) and 1.28mm (16L). Go 1.23mm for a bit more feel and comfort, or 1.28mm if you want more durability from a string that is not the toughest in the bag.

Is Isospeed Cream arm-friendly?

It is soft for a co-polyester and can be genuinely comfortable when strung low in a control-oriented pattern, which is why it appeals to players managing elbow or shoulder niggles. But it is still a poly and it is setup-sensitive — strung tight in an open pattern it can read firm. If you need the gentlest possible string, a true multifilament will be softer.

How does Isospeed Cream compare to Luxilon Alu Power?

Both are round control polys, but Alu Power is the firm, crisp benchmark, while Isospeed Cream trades some of that connected snap for noticeably more comfort and softer feel. Cream is also lower-powered. If Alu Power feels too stiff on your arm, Cream is a logical, gentler alternative in the same round-control family.

Is Isospeed Cream durable?

Durability is its weak spot. It is not a string for frequent breakers — the thinner crosses can file down and snap, and it can move around in open patterns. Its tension maintenance, however, is very good, so it tends to stay playable until it physically wears out rather than going dead.