I've had a RIPP supercharger in my 2009 3.8 for about three months now. Was looking at a V8 conversation but all the kits are for LHD and I'd lose too much dash function to go LS etc
Dyno'd before and after about 50% more hp and torque.
Certainly feels different to drive, more urgent and heaps better on road, up hills etc
Had to have a custom air box made up to plumb my Safari snorkel in.
Saves a couple of l/100km when cruising but sucks more when you put your foot down.