what are the best all motor heads?

[Moxie]

Thanks for the info. I'm not a machinist, so I wasn't aware of that.

As for TFS problems, I have 3 customers who purchased the TW heads when they were new a few years ago. One guy had wear problems because the heads had been assembled with steel valve guides instead of bronze. TFS replaced the parts under warranty. My other 2 customers sent their heads back for the same reason, and TFS took care of them as well. Since then, the TFS heads haven't caused any problems. TFS now installs bronze valve guides in their heads.

I understand some other people have had issues with the TFS heads, however in my indirect experience, the guys here haven't had any serious problems with them.