Different Carb or EFI

I had this plan to save up for EFI. I currently have a 750 dp that I wanted to put on top of my 410 stroker, but thats if I cant find a 950hp. My question is what do you guys think would be better in the long run? The EZ kits bolt on and change CFM, so it would save money on swapping carbs, but I think I might have plans for nitrous and I do not know if there is a kit that basically bolts on while being able to use nitrous. This is a 410 stroker that should make 500hp. I seen DVJCUDA has the EZ-FAST but he is not using nitrous. The other thing is I don't really want to do an in tank fuel pump, is it possible to run the kits without it even with a return line?