Bomber

I am trying to see which is better for the money/power ratio , I have a 305 .40 over , comp cams 118/124 @.50 (not sure i dont have the card) untouched vortec heads, 1.5 roller rockers, headers , edelbrock performer intake , and a 650 dbl pumper, my question is which is better for me a 150 shot of nos, or 7-10lbs of boost (turbo) not sure what the turbo is but my brother is giving it to me for free, Thank you so much