Need Advice on Amp Audition at a Dealers

Home audition is the ONLY way to do this effectively. We are dealing with SYSTEMS and theirs is NOT YOURS. Can’t be done? They won’t allow this? Then take your chances and listen to an amp IN THEIR SYSTEM. But you won’t be listening to an amp, will you?

Home demo or audition would be best. That way you get to listen to the new amp vs the one you have now in your own setup, system and room environment using your own cables, front end source components and your own speakers. 

thanks to all who took the time to respond. I've been in the hobby a long time and realize a home audition is optimal.  I am hours away from the dealer and a home audition is just not feasible. I want to hear the difference between my current amp and the one I'm considering. I figure this would be a way to hear "differences" even in a strange room and not my gear. If that's a waste of time I guess I forgo the whole experience. Asking the dealers input and "permission" to A-B is a great idea.

One problem I can see with your idea is that you need to think of the speaker and amp as essentially one component.  Unless the dealer has the same speakers as you do, you will be hearing how your and another amp interact with the speakers they're hooked up to; they may not work the same way with your speakers.  If he has the same speakers as you, then your idea will work well