I didn't mind the extra weight, it ended up being like 80lbs heavier. The iron block has much thicker sleeves, so that's part of it. The main reason I have the LSX is the six bolt heads, they become necessary after that 1000 wheel mark. I'm either running a set of 63s or an F1X with a direct port shot, maybe in the 250 range. To run nitrous and a blower I would recommend that you have the pistons gas ported, it keeps the rings from collapsing and is usually only 15 to 20 bucks a piston. I can't find the picture of mine right now, but this is a great example of them:
I Ain't About That Stock Life.