Engine Buy

I was at the Good Guys Race today at Pomona. I saw the Chevrolet ZZ572/620 at the show. The guys there had it set up to run on a motor stand, sounded sick (good) my wife had a smile from ear to ear, she wanted me to buy it right then and there( am I lucky or what). The motor is rumored to produce 700hp for 13000.00. Now heres the deal. I am new to normally aspirated motors, far as I know World Products kick butt, RIGHT? They have a motor which is the
Hardcore 540/610, probably make way more horses but they are conservitive on ADVERTISED HP so they dont end up in court. This motor goes for about
3 grand less. GM has 12/12000 mile warranty Worlds has 24/24000 mile warranty, am I being rediculous on what the better deal is. Also how do you make this much power for alot less? Is it possible? Thanks.. Oh going in a 72 Chevelle. Also anyone know the weight of my car?

This is just my opinion... But if I was to be throwing that kind of money into an engine bay of an older car, I'd be seriously looking into the LS7 and kicking around the idea of that swap.

*edit* Dang, I just saw that this thread is a month old already...