I'd have to agree with Courier--poly has really helped me hit shots I couldn't hit before. I played D. I college tennis in the early 80's with wood then with small, flexy graphite racquets strung with gut (a very short and undistinguished playing career I can assure you!). Gave up the game in the early 90's, then took it up again a couple years ago. I'd given away my old racquets (Head players frames mostly, with a POG oversize I stole from my dad--wish I still had those frames--they were cool!) so I had to buy a new racquet. I got a pair of LM Prestige MPs and strung them up with gut. Felt good, but more lively than I remembered/wanted. So my stringer recommended I try a fully poly (co-poly?) job--Head Ultra Tour 17 which I put in one frame. Loved it! The poly solved the control problem with my new Prestiges instantly. Much more spin! Much more control! Best of all, I could really swing out and still keep it in the court. Here's the weird thing--I find Ultra Tour poly "deader" than gut for blocking shots and volleys and bunt returns. But I find it more powerful than gut if I swing out on full groundstrokes and first serves. I think this is a great combo--dead when you want dead and lively when you want lively. So it really helped my (admittedly very rusty and pretty mundane) game. I had no arm issues whatsoever with poly, but then I've never had tennis or golfer's elbow in my life. Maybe I just don't swing hard enough to get it? (I'm not a big hitter at all, more of a retriever then as now).
I heard that Luxilon was the bomb, so I strung up my back-up frame with BB Alu Power 16L. I also thought that was better than gut, and nice stuff but I didn't find quite the same precise control I had with the Ultra Tour 17. The BB ALU Power had a bit more power than Ultra Tour, but the control loss didn't allow me to exploit that extra pop very well. I probably could play with the tension and find the sweet spot with BB ALU (I didn't drop the tension at all from gut to be honest--59 lbs with gut and poly alike) but the Ultra Tour works for me and is cheaper than BB ALU Power, so I've stayed with Ultra Tour. I tried Kirschbaum Touch Turbo and thought it played just like Ultra Tour, but it went dead after a few weeks.
That's the other strange thing about Ultra Tour. I've had it in a frame as long as 10 months and it still plays well for me! It measures like 44 lbs now, but it dropped to that after a month and has stayed there consistently. I think the very low tension gives some extra pop but the fatigue in the strings deadens it too, so overall it plays pretty much like when freshly strung--maybe even softer feeling. In some ways I actually like Ultra Tour best after a few weeks and 10 or 12 sets. Tried stringing it low at 52 for starters, but didn't like that at all. Too lively new and old.
Just my $.02. Those of you who were looking for poly recommendations and haven't tried Head Ultra Tour--maybe give it a shot. It's pretty cheap if you don't like it... and seems to have gotten a fair bit of love on these boards...