The worst one I ever spent money on was a "tip burnisher" to eliminate mushrooming that was basically a Delrin plastic sleeve that looked kinda like a joint protector,but was severely tapered on the inside. I cranked down on it too hard trying to get it to work right and twisted a relatively new tip off a Meucci shaft while still waiting on my Schon to be delivered,this was in 1990-91.
I saw those APT tools when they first came out,and knew immediately they would be no bueno,but thank whoever came up with them and it's copies because along with the Tip Pik,these tools have brought me over 1000 bucks worth of repairs over the years because of their improper use. Tommy D.