Aye - that’s best - i never really find any demo nails what I do, but i try to educate myself on the feature set and hear as many parameters available as possible and then imagine within the range of what something does, will it get what I want.
Often things will be derivatives of what is around, Fender tone stack, baxendall, certain power sections etc all have their own flavour, piece em together and finally see what extra the manufacturers may have put in or altered slightly and to get your recipe - it’s why the “ooo what’s your settings” doesn’t really hold water. I’d also wager most amps, especially decent ones will do most types of music if sensibly used