I never had a problem with Thunderheads on game, but I started using Muzzy because I got tired of my T'headsfalling into multiple and sundry pieces every time I unscrewed them from the arrow. [:@]

Muzzy is a much stronger head, much better blade retention system and Ilikethe Trocar points much better than the punch thru typepoints like T'head uses. And you don't have to have them freakin' UBAR's! T'heads are good but Muzzy is better, IMO.

Now I won't use anything but cut on contact heads.