Tension(s) used for playtest: 45 Lbs (JET method), strung with electronic CP machine
Regular string set up: Yonex PTP or PTHS
Racquet brand and model used for test: Yonex Ai98
Power of test string: I found the power level to be similar to other soft polys. It's not a low power, control string....and it isn't a string board either. It's a manageable power level that would be great for first time poly users.
Feel (Stiff? Mushy? Muted? Crisp?): I found Quadro Twist to be muted. I prefer a crisp feel and sound on impact. This string is closer to Big Hitter Black 7 is its feel. BHB7 is very stringy. QT isn't as springy, but I defintely felt like the ball got a little lost on the stringbed.
Spin: I hit with a lot of spin with all strings, so I am not always a good judge for this category. In terms of spin, I didn't notice anything significantly different in spin production. I was hoping to after reading the TW review from Chris and Andy. Spin production was at normal poly levels, IMO.
Comfort: I found comfort right from the start with this string. After having suffered a couple acute tennis elbow injuries in the last 2 years, I am very sensitive to harsh strings. Ytex QT is a nice, comfy, arm friendly string !!! For an all poly setup, comfort is at the top for the poly list. It is as comfy as many 18 gauge polys ( PTP 120 and Prince XT.)
Durability: I had no issues with durability. It notched just like all polys... visible notching in the 1st hour. deeper notching in hours 2-4. after hour 4, notching seems to settle in and not get much deeper. This is about the same for every poly i play though. For reference, syn guts and multis break within 2-3 hour mark for me.
Playability Duration (share thoughts on if/how the playability changed over time): This was interesting for me. In the first couple hours of hitting, the strings felt amazing. great snapback, strings remained shiny, shots dropped into play, etc. In the later hours of play, especially in 3-7, I noticed more flyers, more balls going out, not as much kick on serves. By the 8th hour of play, I thought there was something wrong with my racquet. Any shot not squarely in the sweetspot felt like I was hitting with a 2x4 ! I've never felt that feeling before. It almost felt like when a carbon fiber baseball/softball bat "loses it pop." Not only did it feel weird, the shots sounded odd. I was really concerned that my racquet had issues. At this point, I cut out the Ytex Quado Twist.... and the strings had no elasticity left. cutting the strings only made the strings pull back about an 1/8-1/4" from the cut. That's dead, folks! I restrung the racquet and played later.... the racquet was fine.
Control (predictable trajectory? Easy to control depth? performance on different strokes and swing speeds?): When I think of control, I think of very low powered strings. QT is a good string, but it has too much power to be a "control" string. It is certainly better than playing with multis of synguts. this is a well rounded string with a balance of power, control, and touch.
Compare to the string you use most often: I would compare QT mostly to when I play with a gut/poly hybrid. It has the muted power that a gut hybrid gives you. it also has similar spin production. The gut/poly last a lot longer in terms of playability, but gut/poly is considerably more expensive. I usually restring my poly crosses once before the gut evenutally gives way. Qt would be a great string to get that gut/poly feel but without the cost or care needed for using gut.
Tension recommendations (after hitting it, would you recommend a different tension? Why?): ahh.... tension.... this is where I have a feeling that some guidance from Ytex would have been great. I have a feeling that QT should not be strung at lower tensions (40s). From reading other reviews, there are wildly different opinions on spin production. I think this string was independantly rated for having the 2nd best spin production, too. The only thing I can think of is that this string should be strung in the upper 50-60 range. On some other playtests, the manufacturers have repsonded to threads and given advise or thoughts to the playtesters. I wish Ytex would have jumped in on this one. As such, I bought another pack of QT and am going to test it out at higher tensions. I think there is more to this string than I discovered in my playtest.
A big thanks to Tennis Warehouse and Ytex for letting me playtest this string. Please let know if there is something to my theory that this is not a string that shines in low tensions. I want to find the bite and spin that Chris and Andy raved about. Once I test it out at high tensions, I'll add it back into this thread.