nitrous - more torque than supercharger, lots of power under the curve, cheap, but have to refill the bottle.
supercharger - makes slightly more torque on a 2.5L than some N/A 3.0L's
, boost starts at about 4,500 rpms and peaks at redline, reliability issues, dont have to worry about the refill issue. And just for Greg, "Still outran by a naturally aspirated 3.0L."