Has any one used these on anything yet I'm building a new motor and thinking about going with these heads

Your going to need a big motor for that head.

I'm building a 600" motor

NA or will you be pressurizing the intake?

How much power are you looking to make, and at what RPM do you wish to spin it to?

Na bill and looking for 850 hp at 6500 rpm

In that case, I think you can hit your target with less cylinder head. Like an AFR 357, Dart 355, BBX O 351, etc. Sounds like a cool build, as expected from you western michigan guys!.

that'll work,plus the cam won't be a prostock profile.afr 357's will get you 740-770hp,cam profile will determine the final power.

Dennis for 600 ci the Profiler 355 is a better head. With cam and compression it should go over 850 with reasonable rpm's. The key to making power with these big motor's is valve lift. The more lift you throw at it the more expensive it gets and attention to detail is extremely critical to try and make it live.

Brodix 351cc oval head made 900hp on my injected 598 around 6600. that was a wet sump oil system. If you want any other specs PM me
One more thing I would not go to big on the runner CC. Will make it a turd on the bottom end.