Roy Poper endorses the following products and companies:
Ken Larson's BrassWerks
"Ken Larson's GFT trumpets are among the very finest made today. I have three of them (the Bb, C, and Eb/D) and they all share the superior qualities that Ken's instruments are well known for: excellent pitch, great tonal balance, and accurate response. These are truly 'musical instruments' and assist the player in creating artistic performances. I couldn't be more pleased."
Balquhidder Music
Publishers of music and excellent method books for brass instruments.