"It's great!..makes my old Horn competitive in the new Horn market" 
...Marshall Sealy, NY Freelance French Horn Artist. 

"Hey, it's turbo-charged!"
....Tom Baker, Lead Trumpet, Joel Kaye's Neophonic Jazz Orchestra

From Jan Lhotak, a free-lance trumpet player in Omaha, NE (member, AFM local 70-558) on his LA Benge 3X plus using a stock 3C Bach mouthpiece......
"One word: INCREDIBLE! Broken down, here's what changed:
1. Better, more balanced intonation throughout the entire range of the horn. It's (now) a joy to play at all volume levels. 
2. With the coil in the upper tube, I love the slightly increased resistance. Since I don't play very often, it makes my playing easier.
3. From the player's perspective, the horn has a much more focused, centered sound with more sparkle to it. the sound quality also seems warmer and definitely projects better. 
4. From the listener's perspective, my wife (and biggest fan) says that my horn sounds brighter and fills the room better, especially in a large hall. 
5. Here's the caveat...boy, am I glad that you warned me about overshootng high notes. Last Sunday I played lead with a local dance band and I really had to watch it! I did miss a few high notes, but it was great to miss them on the high side instead of the low side.Three hours into the gig, the leader called up "In the Mood" (God only knows why they all do it) and for once in a long time, I was able to nail dead solid the high D at the end! 
6. Since I prefer playing small combo jobs, I love the way my Benge plays now. It's perfect for everything from Bobby Hackett style solo ballads to Dixieland. Bottom line: I can't thank you enough! You saved me the heartache of giving up my beloved Benge, not to mention the expense of buying another horn. Quite a difference, $37.00 versus $1000+++!" 

Richard Kelley of the Boston Brass says "...makes my flugelhorn play easier and better in tune".