I have used Warburton mouthpieces on and off for about 15 years now, and recently tried this backbore on the recommendation of an esteemed colleague.
I was using a 5M/NY setup for lead type playing, and decided to try the KT* as i was advised I would probably find a benefit in greater projection and volume of tone as well as more endurance.
Straight off my endurance was not better, but true enough the sound was more focussed, projected better and much fatter overall. After 2 weeks of getting used to the backbore, learning that less is more in the response of the backbore, i did then get the better endurance.
I found this to work surprisingly well on piccolo trumpet with the MD cup Warburton offers. Rarely do I find a commercial backbore to work on piccolo, but this does.
