poly mounts - pros, cons
the poly mounts aren't for evryone. The GN I have currently had the driver's side polyeurethane mount from HRPartsNStuff. Extremely high quality part (all their stuff is), but the poly mounts are so stiff, they transmit a *lot* of engine vibration to the rest of the car (you can really feel it!). I drove the car that way for a few months and decided that was enough. I pulled it off and replaced both mounts with OEM type rubber mounts and a torque strap.
A torque stap isn't as strong, true, but it was a night and day difference in how much smoother the car *felt* while sitting in it. IMO, it depends on what you're doing with the car. My car sees more street time than track time so I like it more comfortable. If I was making more power and took it to the track more often, I'd probably go with the poly mounts.
As for installing the strap, it is easy - just re-read the instructions and take a good look at the holes in the frame. I'd snap a picture for you, but the battery in my digital camera just went belly up yesterday.
HTH
Rob