The reason you do not have a lot of responses on the MPI supercharger is that most of us got them too late last spring to get any time on them. Mine went on fine and quality of workmanship was great. I had plans to set it up for tar, but work got in the way. I can not brag on anything else because of lack of time on unit. The old saying is to brag at the end of day when you have it back on the trailer, so I guess we will wait a little while. I plan to ride at either 5lb or 7.5 lb boost at 1000 ft on pump gas. If I go 7.5, I will probably have some better gas around if needed. I have MPI air/fuel gage, a boost gage, and a water temp gage installed to monitor things. Where I normally ride, lack of snow can be an issue, so I will stay at a reasonable boost level. Even the minimum 180 hp is a tremendious horse power to weight ratio increase. We stud heavy and ride mostly lakes, so I wanted the throttle response of the Supercharger. I can see the use for higher numbers in deep powder or at higher elevation. At 100 degrees here lately, it is hard to get too excited about wrenching.
Doug