PA , Glass calls come in different grades and sounds and I depends on the sound and ammount of $$ you want to spend. I can not speak on the other companies and do know there is some good sounding glass calls out their, but I have used the QuakerBoys Eradicator with success in both the Field and on stage. One of the main points of a good glass call is to condision these such calls proper for the proper preformance. Using sanding stones will change the way any of the glass calls work and aswell the proper pick of wood strikers on the sufface. Sand paper on glass is a thing of the passed, but look around and condision and use each call and get a proper hear of how the call works...BT