As with bullets, arrow placement is all important. Check your local laws. Here there are minimum size requirements.
I know a bear hunter who uses a bow, and those tips are just larger than the arrow shaft (illegal for deer) but larger does not penetrate as far.
Larger heads make a larger hole, and do more damage at shallower depths, so it is a trade off.
I use mechanicals nothing fancy, silver strikes, with about 1&1/2 dia. Cut, i think. Same on my bow and crossbow.

Edit: http://www.archerytalk.com/vb/showthread.php?t=774418#/topics/774418?_k=f7j0of

These guys are discussing silver strike tips.

Last edited by kellory; 10/30/16.
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