I figured I'd save some space and deal with two problems/questions in one thread. During rehearsal today, I noticed my mouthpiece was looking pretty tarnished, so I cleaned off the tarnish tonight. However, I noticed at the very end of the shank that the mouthpiece looks almost rusted - there's a thin line of rosy-bronze discoloration at the end. It doesn't look or feel like anything's caked on, so I'm wondering - is the receiver somehow stripping the silver plate from the piece? I pulled out my old Getzen 7C that I used with the same horn before this one, and it has the same line, but thicker and more pronounced. What's going on here? I'm pretty ticked - this Bach 3C's only about 5 months old. Also, it dawned on me the other day that if I do manage to convince my parents to take me trumpet shopping for a pro model around Christmastime, I know I should try to look at all the horns in my price range, but what should I be listening for when I try out new horns? What are things that I should feel for when I'm testing these horns? What are some good things to play to test the horn? Etc. I've never actually tested a horn before; I've just been handed the rental I've been playing on for 5+ years. So any tips on that front? Thanks in advance for both of these questions.