I have five Monette trumpets. The first four came with all the same valves. When you give the trumpet a bath you are supposed to change the felts on the valves. They give you a bunch with each trumpet and if you need more, they are free.
When I got my MF trumpet I never looked at the cleaning kit that came with it. I just put it away with the others. It turns out that the felts on this trumpet are different and after my first bath I was using the wrong felts. To look at them they are clearly a different thickness. I just played my trumpet and didn't notice a difference. Today I put the correct pads in and again, didn't notice the difference.
I guess a precision valve alignment wouldn't help my playing.