- RST X-4 Squad

First Impressions
The Roto Grip RST X-4 Squad presents itself as a powerful addition to the RST series and stands out visually with a striking color scheme in black and two shades of red (Black / 2-Tone Red). Unlike the regular RST X-4, which comes with a pearl cover, the Squad edition uses the aggressive "Hyper Response Solid Reactive" coverstock. Inside sits the proven asymmetric RST™ core (Roto Star Tour), which already caused a stir in the previous models. With a 2.53 RG and a 0.053 differential (at 15 lbs), this core delivers a medium moment of inertia that promotes quick rotation, while the significant asymmetric differential of 0.016 provides a defined change of direction. The combination of the tacky solid surface, often delivered out of the box with a matte finish (e.g. 2000-grit), and the dynamic core should make the ball read the lane earlier than the pearl version without burning up energy in the backend too soon.
Comparison
Compared directly to the standard Roto Grip RST X-4, the Squad version shows a noticeably earlier reaction profile. Where the regular X-4 with the eTrax Pearl cover skids longer through the heads and shows a very angular reaction at the breakpoint, the RST X-4 Squad offers more traction in the oil and a rounder but still powerful arc thanks to the solid cover. It behaves similarly to the Roto Grip RST X-1 (hybrid), but the "Hyper Response" base chemistry gives it a quicker response to friction once it exits the oil. Against the Roto Grip Attention Star (released around the same time in January 2024), which is designed more for length and backend, the RST X-4 Squad positions itself as the more stable ball for fresher conditions and should be less prone to over/under reactions on difficult patterns. It fills the gap for bowlers who love the RST core but need more overall hook than the pearl version provides.
On the Lanes
The Roto Grip RST X-4 Squad is made for medium to heavier oil volumes. Thanks to the solid cover, it works excellently as the first ball out of the bag (benchmark ball) on a fresh house shot or on sport patterns where midlane control is required. The ball's strength lies in its ability to handle the transition of the oil pattern: it reads the lane early enough not to skid, but thanks to the RST core it retains enough energy for a strong drive through the pins (carry). If you throw the ball at higher speed, you'll appreciate the extra traction of the surface to get the ball working in time. For rev-dominant bowlers it offers a controllable option that doesn't react as abruptly to dry boards as pure pearl balls do. Once the lane breaks down over the course of the game and the heads dry up, a switch to the regular RST X-4 or a symmetrical ball would be advisable.