Re: Have a question about selmer mouthpieces.
I don't disslike the S80 as much as some, but I do agree that there are a lot of other mouthpieces to be had and witch should be tried. I've read where a number of mouthpiece experts that the square chamber of the S80 messes with tuning, among other things.
From what I can guess, you were told about the S80 by an instructor. They are all the rage in the minds of music instructors for some reason, and they tend to be a decent 'default' step-up piece for concert work. However, if you're going to pay you're own money for the S80, you might as well try it along with some other pieces to make sure you're the one pleased by it's purchase. I can suggest a few that are suitable for concert alto work:
Try each in as many sized (tip openings) as are available. I find the soloist gives better projection and a darker, more focused sound than the S80. It's very flexible in what you can do with it. The Optimum is darker still with equivalent projection of the S80, but in it's AL3 opening, requires a more openfaced embrochure from myself, yet tone production quite effortless. You could try that or the AL4, which has a slightly more open facing.
I also can suggest the Soloist for tenor work, as well as the pricier Metal Classic from Selmer.