i use xr shafts and vibratechnic mounts, no problems what so ever

though i havnt gave it a proper full launch yet as i like my gearbox and diffs lol

once these are sorted il give it ago, im also going to be going the skyline route as soon as my box gets destroyed, though im not running as much power as yours yet, im running around 380 -400 but the engine is built for 500, so only a matter of time to get the full potential out of it