Polyester strings are celebrated for their durability, control, and spin production. They’re manna for heavy-hitting baseliners. However, there are two noticeable drawbacks to the strings. First, many, particularly the monofilament variety, can be rigid and tough on the arm. Most players need to string at lower tensions to alleviate the stiffness, which brings us to problem No. 2: polyesters have lousy tension maintenance. If a player is stringing at a lower tension to begin with, and the tension drops significantly after only a few hours on court, the racquet can turn into a slingshot. And if you opt for one of the softer, multifilament polys, the stringbed can start to feel like mush.

Although technically not made of polyester—as anyone from Wilson, the string’s distributor, is quick to point out—Luxilon strings share many of the same characteristics as polys. Their new 4G line has been designed to lessen the tension maintenance problem. Fans may have noticed the gold-colored strings in the racquets of pros such as Serena Williams, Kei Nishikori, and Grigor Dmitrov. Most of these players have the luxury of using freshly strung racquets, making tension loss rarely an issue. But for mere mortals who prefer at least a few weeks between stringing, it can be a definite concern.

I had the 4G strung in my frame at 53 pounds. Lately, I’ve been using softer polyesters, such as Volkl Cyclone Tour and Solinco Tour Bite Soft, and have been stringing around five pounds tighter. But since the 4G is a firm monofilament it seemed wise to drop tension. It was the right move. From the first stroke I noticed a stiffer response than what I’d been accustomed. This became less of an issue after a short break-in period—which I find typical of Luxilon—that might have been lessened further by dropping string tension even a few more pounds. Or it might make an excellent candidate as the mains in a hybrid. My racquet has a 16-by-18 string pattern, so I can get away with using it in the entire stringbed. A player with more cross strings may want to combine it with a softer string, or drop the tension into the upper 40s.

From a performance standpoint, there’s no easy power with these strings; I definitely had to work a little harder to put pace on my shots and aim a little higher over the net for better depth. And that wasn’t necessarily a bad thing. I liked having the freedom to take a healthy cut with the belief that I had the spin and direction to control my shots. This felt particularly true on the forehand side where I could really go after the ball and was rewarded with good pace and heavy spin. Not surprisingly, it’s a string for heavy-hitters who want to put a lot of work on the ball. It also gives you those great “Luxilon” shots: I’d miss the sweetspot and the ball would sail, but someone have the necessary spin to drop deep in the court much to my opponent’s dismay. It’s a string hallmark.

The serve was a mixed-blessing: I couldn’t generate as much pace, but had dependable placement and lots of kick. Same with the backhand. Touch shots are the weakest part of my game, so I wouldn’t offer a good reading on how the string performs in the feel department. However, I did find I could really stick volleys and direct them where I wanted to.

In terms of tension maintenance, after two matches and several hours of play I didn’t notice much difference in playability. I can’t say the same for many of the other polyesters I’ve tried. After the same amount of time I’ve often had to dial back my aggression or add extra spin to keep balls in the court. I’ll probably still want to restring the racquet after a couple of weeks, but I have a suspicion I won’t feel like I have to.