I have been using one with small pistol primers and it has worked well. It took me awhile to get the alignment just right, but it has bee fine since then. The instructions advise not to over tighten the bolt that attaches the unit to the press. This lets the unit move out of the way should it make contact with the primer cup, or anything else, and reduce the risk of crushing a primer. It took me a few tries to get the bolt tight enough so it did not loosen during normal use, but not feel like I was over tightening it for safety. Once I got that correct it has been operating just fine, even during primer tube replacement. I am glad I made the investment.
I still use my hand primer now and then, but have been using the auto feed more and more.
I make sure the primer tube is pointing in a safe direction should a primer detonate. I also clean the primer tubes periodically to remove any primer dust.
Hope this helps.
