Not surprisingly, Duo Power gave our playtesters more power than they get from their preferred polyester setups. For Chris, the extra power came with some challenges, but he ultimately found a groove, especially after dialing in the tension. He noted, "Being as this string has power in its name, I expected some pop, and I was not disappointed. I liked the power level of this string a lot when I was looking to put the ball away. I also found easier access to depth than I typically get from a full bed of co-poly string. The downside was that I did not get quite the same level of control, and it was just a little easier for me to overhit. While I had a lower trajectory from Duo Power than I do with a full set of ALU Power 1.25, I didn't get the bite to help dip the ball inside the lines. With that said, control was still pretty impressive, and going up 2 pounds in tension helped even more."

Ever the technician, Mark fine-tuned this hybrid's response by putting ALU Power in the mains. He described, "I decided to run the ALU monofilament as the mains and the NXT for the crosses. This gave me plenty of control and predictability, with the NXT supplying great feel and more-than-sufficient comfort. This setup was more powerful my usual full bed of polyester, which made it a little easier to hit with depth."

Given how dependent spin generation is on individual stroke style, it's not surprising that our playtesters came to different conclusions on Duo Power's spin potential. Of the two testers, Mark found the most success on the spin front. He said, "With a tight 18-main string pattern, getting a grip on the ball is not always easy for me, so I am keen on any string setup that affords me better spin potential. I typically play with shaped strings, so I was thrilled that the ALU/NXT combo delivered a manageable launch angle for easy shot clearance over the net and plenty of ball rotation to keep the ball diving inside the lines. Although sliced shots do not arc, I got the same result in terms of both string materials sinking into the ball, allowing for effective driving or slice touch shots."

Although Duo Power gave Chris sufficient spin, it stopped well shy of earning a full-throated endorsement in this category. He described, "One of the things I love about hitting with ALU Power 1.25 is the spin I get from the stringbed. Mixing it with NXT Power in this hybrid lessened the spin potential somewhat. I went with the ALU Power in the mains because I wanted to get as much control out of the hybrid as possible, and the NXT Power cross string was inhibiting spin snapback. While a full bed of ALU Power can slide easily and snap back for added spin, it got hung up on the NXT Power and stuck out of position. I would say I mostly got spin from the controlled nature of the string allowing me to swing quickly, rather than getting assistance from the stringbed itself."

Duo Power includes one of the game's most plush multifilaments, so it makes sense that our crew gave this hybrid high marks for feel and comfort. Even Chris, who typically uses a much stiffer setup, appreciated the softer response of this hybrid. He said, "I enjoyed the feel of Duo Power. The stringbed felt softer and more forgiving than I'm used to thanks to the inclusion of NXT Power as the cross string. The stringbed felt like it was pocketing the ball well, and I had a lot of feel on touch volleys."

For Mark, the feel and response of Duo Power was not only comfortable, but it also felt great across a variety of stroke styles and court situations. He said, "With the presence of NXT, the Wilson Duo hybrid offered great comfort, and the presence of ALU Power helped give it a controlled feel. Whether I was driving the ball from the back court or the situation required more touch than power, the versatile Wilson Duo Power hybrid reacted like a volume control and was adaptable to that variety of play."

According to our playtest crew, Duo Power held its optimal playing characteristics quite well over time. Granted, Chris noticed some tension loss and frictional notching (on the cross strings), but neither of these things compromised performance or led to premature breakage. He explained, "I found Duo Power to last well. I did not break either the mains or crosses, but the NXT Power crosses got pretty notched. Since I wasn't getting much snapback from this stringbed anyway, the notching did not noticeably alter the playability. After an initial drop in tension, which is expected with any string, I found the response to feel pretty consistent for the duration of the test. I had Duo Power in a couple of different racquets. In my Tecnifibre TF40s, we initially strung Duo Power too tightly at 54 pounds, but after the tension dropped and the string settled in, it felt great for the next two weeks. However, my favorite tension was at 50 pounds, and I found the stringbed to pocket the ball very nicely once it had broken in."

"I did not notice any playability issues over the course of the playtest," added Mark. "I do not 'crush' the ball, and my tight stringbed helps prevent excessive wear, but I have to say that the response was very reliable and predictable over the entire length of this playtest."