You haven't mentioned how you intend to use your car, but let's assume it will be a cruiser/tire burner. If that's the case, then 300-350hp is more than plenty IMO and it's much more budget friendly.
Of course it's your money, but some other things need to be considered when the HP approaches or goes beyond 350-400 : rear, transmission, torque converter, brakes and suspension. Your stock, or mostly stock components, will handle up to 350 hp for a long time in stock form. You can spend a pile of money upgrading the trans and rear alone. Again, maybe you have already considered these items, but maybe you haven't. Either way let us know, or at least consider everything that will need money.
Good luck - Jim
I considered all of that. same as my 01 camaro SS once I got higher power I upgraded everything else as well. It is def on my expense list. but im less concerned with those aspects than the initial engine decision.
I just happen to run into some G body people today when I was racing at street wars at E-town and apparently the proformance unlimited that is located by he he has heard very good things about so we will see