My butt is very particular about saddles. As above, I know by now what a candidate saddle looks like. The LBS trial method works well if they happen to carry the sort of saddle you need. The method I now use is to order 3 saddles at a time from Performance, try them all, then wash the ones I don't want, put them back exactly in their original packaging including zip ties, and return. I'm out the postage but it's totally worth it to me. I've gone through many triples from Performance.

Why would I need a new saddle? Because as one ages or changes in body shape, one's saddle needs can change. Plus I wear them out. Usually by the time I wear a saddle out, that model is no longer made or no longer made just the same, so I'm back to searching. When I find just the right saddle, I buy one for every bike plus a spare.

My best luck at saddle testing has come from riding hilly centuries on a trial saddle. My opinion is that you won't know if it's going to work for you until after the 3rd hour.