340 Aluminum Head, Rocker Arm Upgrade
As with most things. What you should or would buy is dependent on what you expect as a result. SM's are cheap, can be fixed up and still cost mush less than some alternatives and provide solid output. Just depeneds on where you want to spend your dollars.
Looking a for a streetable 500hp SB engine, lots of OEM style heads fit that bill.
TF have always been nicely machined regardless of product line (GM, Ford, Mopar)