I have the 440Source 528 kit and had no issues with it at all. HOWEVER, do youself a big favour and have your block sonic checked first to make sure it can take the bore you want to go with AND have the deck heights checked first as well. My "stock" block ended up having the decks below spec before decking so I'm having to run a tighter quench than I would have liked. Had I checked that before ordering my kit I could have ordered a different piston and not had an issue. Also, go with aluminum main caps. Yes, its more work, yes its more money and yes, most engine builders will tell you they aren't necessary BUT they're used to building Chevy's. Aluminum caps in the RB is cheap insurance. The 440Source ones seem decent for the price.

Doing it over again I'd go with the 512 instead of the 528.