SC14s are unpredictable i wouldnt boost them over 5psi, they are loud, but when you move the throttle body it makes it alot more quieter and power delivery is abit delayed but better i have some vids on youtube you should check them out, i never got it running right on higher boost but the sc14 was on its way out and teflon wen everywhere lol.
I chose to go Turbo Because you make more power on lower boost its not asloud as the sc14 and to cruise normally its more driveable appose to the sc14, even if you have the sc14 turned off on the switch the motor has to suck through the rotors and you loose power and put the motor under more strain.
I will give you a better answer and i will have alot of vids when i get it on, i just have to pay rego and start fitting eveything up.
But like i said if you get a cheap sc14 run it at 5psi with or without an intercooler, you will net 150-160rwkw and with a drag car and slicks easy get a mid to low 8.
http://www.youtube.com/watch?v=KrX2sNLA6vw