I have used them all Valvoline, Joe Gibbs, Brad Penn, Torco, Amsoil and LAT.
This is my ranking:
1.) Joe Gibbs
2.) LAT
the rest are tied and all good oils.

Flat tappet cams are a tuff deal. I recommend hyd rollers anytime I'm asked to do a flat tappet. It's always about the cost but in the long run one flat cam and the hyd roller pays for it's self.