S/C is lower initial investment into your project, the single or twin set-up will be more costly initially but have substantial increase in headroom down the road.
We have been working hard with one customer to acheive 500whp on his Stillen supercharger kit. Looks like it might happen this afternoon on the dyno, but it has been a tough road to get there from the base kit. The TT kits we have done you just need to add a boost controller into the mix and re-tune.
Thanks,
Alex Goodwin
AlexG@motionlabtuning.com