VPA, Tuffhead, Alaska Bowhunting Supply, Silver Flame, Abowyer, and Grizzly are some of the premium (and expensive) heads. Lots of other good two blade heads are out there (almost too many to mention) that are less expensive but perform very well depending on what you are shooting. Some folks here brag about the STOS, Ace, Tusker, Zwickey and others for toughness and penetration on big animals, but except for the STOS that David Stinson has tested extensively with buffalo, I would not say that the other non-premium heads will stand up to the bones encountered in hunting really heavy animals. Then there is the issue of whether to use single or double bevel blades. Right now I plan to use VPA 300 grain double bevel Penetrator broadheads when I return to Australia next July to hunt Asiatic Buffalo again, but that may change as more information comes in about these and other broadheads and as I continue to test various heads myself.
Allan