Yamaha Valve Guide Flugelhorn

After reading a review on here suggesting replacing the stock valve guides on the Thomann Flugelhorn with these ones, I gave it a try. The plastic is certainly stiffer, but to make it fit with the Thoman Flugelhorn you need to get a modelling knife out and cut away at the notch to make it fit. So whether it's good depends a lot on your craft skills. In the end, I found it didn't make that much difference - the valve still stick and need a lot of maintenance.