Originally Posted by AndyMC
I find it tends to go the other way that the more tension the longer they last as the impact is spread out over the whole head more efficiently.
Absolutely, I've never seen a dented tight head. I've seen dented Hydraulics, tuned JAW.
A more uniform collar would probably help with lower tunings, but any collar leaves more room for manufacturing error than no collar. If anybody knows of a collarless batter head, let me know. I'm curious to try one.