As I've said before, I have had the ability to play all the brass horns from piccolo trumpet down to BBb Sousaphone, and many times doubled on trumpet and trombone. However, in my comeback from my medical "mess" my attempt to resume playing the 'bone was horrendous, not because of the mouthpiece but in my slide positions. I put the 'bone away quickly (and am considering forever and liquidating it) and then proceeded to resume playing my euphonium as uses the same 6.5 AL (or 12C) with about as doable results as I've known I could. I just never had a problem with much fall back in only a few days, but a few years during which I was recovering nearly but me back to square one and I presently feel I've forever lost about 20% of my former optimum (my best, not necessarily the best) capability. It will be after Nov 15 that I attempt to resume practice on my picc as has been dormant for going on 3 years other than my maintaining its lubes. It will be a squish to squeeze such in with the load I'm taking on for the Christmas season.