Bob Reeves Mouthpieces are rated as one of the best in the world. The engineering quality is about the best I have seen.The 692S backbore is ideal for large bore free blowing horns and gives a solid top register. The negative side for me is the 28 throat which I found very stuffy, But as for the Bob Reeves Mouthpiece designs in all I would say they are one of the best on the market, anyone out there thinking of a change should give Bob Reeves a try !!!