I am using Hammerheads for the first time this year. I have used Wasp Jakhammers in the past as well and they work good too. I think the Hammerheads open a little quicker and are a little bit wider, plus they are quite a bit cheaper than the Jakhammers. The Hammerheads have 2 slots for the rubber band, one closer to the point and one farther back if you are concerned about having enough KE. That' s my 2 cents worth. Have fun!