Nothing wrong with a good solid flat tappet cam. And the TF intake will work just fine at 600+ hp. If you want to push the engine up close to 700 hp then you would need a roller cam and a MW intake.

Trick Flow made close to 700 hp with a pump gas 505 running the 270 heads with a Trick Flow intake and a 950 carb. They used their hyd roller cam for that test. I think they made 680 hp.

If everything is dialed in correct on your engine then it should pull past 600 hp. You just need to double check everything on a new build.