Hello. I read that chemical cleaning can sometimes cause valves to start skicking a lot, but I went for it anyway. I'd gotten my trumpet chemical cleaned a few months back and ever since, my first and second valves have been sticking like crazy! Valve oil helps for about five minutes, and then they start sticking again. My horn is beautiful though! But, I'd much rather have a horrible looking horn that works well than one that is beautiful, but doesnt work well. I definitely don't plan on getting another chemical clean, but many people have said that their horns came out fine. No problems with them whatsoever. Maybe I was just unlucky. I wouldn't reccomend it, but chemical cleans can be hit and miss, so if you want to go for it, by all means, go for it. I've never uised ultrasonic cleaning, but maybe I will next time.
-Jason