I had all 3 JBR 88's for 3 years and 28k or so miles. Vibes didn't bother me, it's the nature of stuff mounts on any platform. Shifting started getting moody, realized the trans mount bushing started getting deformed. Switched to the DM's and never looked back. Hands down my favorite mod to this car. Vibes were a lot less and the mounts limit engine movement better. Traction, shifting, reduced acceleration thrust, and reduction in noise are just amazing.