Camshafts, head work, and many other rule-bending modifications are ignored because they don't make that big a difference. Every Neon owner there, even those who went to Nationals this year, was interested in the mount. At Watkins Glen, the mount seemed to help turn-in and the car felt more predictable on the edge. Gone was the 'wind-up' of the motor and driveline during downshifting at high speeds. Overall, the mount has few shortcomings.
Increased vibration is an issue with some people.
The vibration can be felt in the steering wheel and seat, and if any piece of trim is prone to rattle, it will. I don't find the vibration objectionable, but I'm willing to accept a little vibration if it means a better performing vehicle. Installation is simple, a 15mm socket, a six inch extension, and a rachet is all that is needed. No jack is required. Remove the two nuts and one bolt that secure the mount to the frame of the car.