Even MB are going to turbos from superchargers for the V12 !
Turbos are more efficient and have virtually no parasitic drag !
I had 2 options for my Rover - turbo or S/C - I chose the turbo because I wanted big power - the S/C just cant develop big inlet pressures due to the charge temperatures getting too high
I will be running a chargecooler as well as the big intercooler in the summer - with a S/C on my particular engine - I couldnt have either
My 1600 currently produces 268hp - so 500 out of 3.6l shouldnt surprise you - there are lots of 500hp cossies out there - and thats from 2.0 !!
The place where superchargers win is with top fuel dragsters, here the drag of the S/C is normally in excess of the power output of the original big block V8 !! - however running nitro by the bucketload helps keeps temps within reason !