I spent the last few months trying out poly strings for the first time. I am not a frequent string breaker and an all Prince Synthetic Gut Duraflex typically lasts me about 4 weeks when I play 3 times a week. Although I hit hard ground strokes with varying degrees of spin, I am a serve and volleyer, which means I don't spend much time hitting groundies, which keeps me from breaking my strings left and right. Although I like PSGD a lot, there's one thing I don't like about it--excessive string movement. This is actually the only reason I decided to try polys in a hybrid setting. So I tried Prince Polygut ($4.99), Gosen Polylon Ice ($2.99) and Ashaway Monogut ($3.99) in the main and PSGD in the cross. All these strings are 17 gauge. I've tried each string twice, and here's my take. String movement: All three are superior to PSGD and hardly move. Polylon is the worst of the three, though. Tension retension: Here Polygut is the best. Very predictable and maintains tension throughout its life. Monogut loses its tension somewhat steadily but it's not that noticeable. In fact, Monogut will feel dead before it loses a lot of tension. Polylon is the worst in terms of initial tension loss, but once it settles, it maintains its tension very well. Durability: All three are about the same. I don't break the poly main. I either break the PSGD cross or have to replace the poly main because it feels dead. Strangely enough, I get a little less life out of the hybrid than from a full PSGD job. Polylon: extremely durable but shreds the PSGD cross like crazy. Polylon takes the outer coating off the PSGD and exposes its soft core in no time. If it were possible to replace just the cross, Polylon would last twice over. Or if I could find a cross that plays as well as PSGD but lasts longer, Polylon would definitely be a contender. Monogut: very easy on the cross but goes dead after 3 weeks. Polygut: like polylon, it causes the PSGD cross to fray but not as badly as Polylon does. In a hybrid setting, this is the most durable of the three. But all three lasts me about 3-4 weeks. Ease on the arm: I had to drop the tension by 5-10% on the main. Monogut is the best here, because you can drop the tension more and still keep the ball in play. Then comes Polylon, followed by Polygut. But from what I hear, these are some of the softest poly strings you can find. Playability: Here Monogut wins hands down. The best feel out of the three in everything: serves, groundies, volleys. I like Polylon next, followed by Polygut. Conclusion: My choice is Ashaway Monogut. I guess I prefer playability over durability (and the differences in durability, as you can see, are rather insignificant). But if I can find a cross that is more durable than PSGD 17 but plays just as well, then I would also consider going with Polylon, or maybe I would just string one of my racquets with Polylon and use it as a rally/practice racket.