With its low power and ultra predictable stringbed response, Blue Rock N Power Hybrid earned a nearly perfect score for control. Michelle, who is a sucker for any string that gives her the control to swing big and crush the ball, had no complaints. She explained, "As a big fan of low powered control strings, I loved how this hybrid allowed me to attack the ball with total confidence. It enabled me to swing bigger and add more of my own power, which fit right into my game. The high spin potential definitely helped bring the ball down. Even when I didn't get a hold of the ball as cleanly as I would have liked, I found the ball was staying deep and jumping up and out of my opponent's strike zone. It reminded me a bit of Weiss CANNON Ultra Cable, which I appreciated because it was so low powered and loaded with control. "

Chris was also impressed by this hybrid's control, especially in the beginning of the playtest. He said, "I liked the response of Blue Rock N Power Hybrid because it was very control oriented. When I was taking a full cut at the ball I felt confident my shots would land inside the lines. There was enough give to the stringbed to keep me connected to my shots, and I felt like I could gauge depth and accuracy very well. When the strings were fresh I found the power level to be low. However, after two weeks in my racquet the strings had lost enough tension to make them too powerful. On my second stringing I had both strings installed with a 20 percent pre-stretch, which took care of the tension loss and kept the strings feeling very control oriented for a solid month! I was able to drop down to 42 lbs in my Pure Drive Plus and find a high level of control with just the right amount of power thanks to the pre-stretch."

Even our resident flat ball hitter got big spin from this hybrid. Michelle explained, "As someone who doesn't necessarily take advantage of all the spin available, I definitely appreciated the amount of spin I got from this hybrid, and I never had any issues with a weird launch angle. The main strings are super shaped, and I could sense how effectively they were grabbing the ball. Even when my contact wasn't perfect there was enough spin to get the ball jumping and moving out of my opponent's strike zone. This really helped when I was a bit late or just being more defensive because I could buy time and work myself into an offensive position. I also appreciated how effectively the ball dipped on service returns. There's just a lot of spin to be had here."

Built from two firm poly-based strings, Blue Rock N Power Hybrid is not supposed to offer the plush comfort of a natural gut or multifilament hybrid. Having said that, our team gave it a pretty respectable score for comfort. This is partly due to the fact that Weiss CANNON has constructed both the mains and crosses with softening agents. Of course, Michelle tested the limits of this hybrid's comfort by installing it at her typical high tension. She explained, "I string my polys tight, and I don't normally experience any discomfort. At 60 lbs I didn't really have any comfort issues with Blue Rock N Power Hybrid. There were a few times when I was warming up into a hit and I felt a pang in my wrist, but it was nothing detrimental, and I was never sore as a result of the string. It definitely is a firm playing option, so I would be cautious stringing it in stiffer racquets at a higher tension, but if you are a player who normally uses firm strings strung high, this hybrid should work just fine for you."

Chris rarely has comfort issues with poly-based strings, and this hybrid was no exception. In fact, he actually stiffened the feel by pre-stretching it during installation, and he still had sufficient comfort. He said, "The first set of Blue Rock N Power Hybrid felt fairly soft in my racquet, but it also bagged out too quickly for me. I had the second set strung with a 20 percent pre-stretch, and it felt much firmer. However, even with the pre-stretch I found Blue Rock N Power Hybrid to play with ample comfort for a poly-based string. I lost a little ball pocketing, but I liked the more consistent feel of the stringbed."

Our team gave Blue Rock N Power Hybrid a great score for feel. It was firm enough to transmit the direct feedback of the ball, but it never felt dead or unresponsive (which is a very common downside of poly-based strings). Chris, who typically uses a fairly stiff poly, had no complaints. He said, "Blue Rock N Power Hybrid offered an enjoyable feel. I felt connected to my shots without getting too much harsh feedback. The string pocketed the ball well, and I had excellent control on my touch shots."

For Michelle, this co-poly hybrid played firm and consistent. She explained, "Firm. There's no doubt about it, this string played firm through the playtest for me. Granted, it was strung tight, but the string characteristics are that of a firm, low powered poly. The stringbed played consistently as well -- even when I wasn't making contact in the sweetspot the strings were just as responsive and consistent."

A common complaint against co-polyester tennis strings is that they lose tension fairly quickly and become unplayable long before they snap. Every co-poly we've tested has this problem to some degree, and Blue Rock N Power Hybrid is no exception. The good news, according to Chris, is that there are things a player can do to minimize the problem. He explained, "The playability of my first set of Blue Rock N Power Hybrid lost tension quicker than expected. After two weeks of play the stringbed was feeling loose and springy. I had lost some depth control and wasn't enjoying the string as much. The second set was installed with a 20 percent pre-stretch and lasted the remaining three weeks of the test and beyond."

"I thought it was about average," said Michelle. "After three weeks, I definitely would cut the strings out and start fresh because I could feel that they had bagged out on me. I started to feel disconnected from the ball and I really had to swing hard to get the ball to penetrate the court."