1, not if you have a turbo!

the pourpose of the m-mounts is to reduce the movement of the motor and it stiffens up the chassie a bit also. You might get a small reduction but the goal is to eliminate the trans from smacking the x-member and cracking it.
2, sure for alot more $ JWT and PR sell them
3, $29 for the f/r $29(?) for the l/r
Mike