I've found that I can be reasonably comfortable on a pretty wide range of saddles, but there are also some that I just can't tolerate. The common factor for me seems to be saddle width. Narrow saddles don't work for me. I went to a Specialized dealer and set on their ass-o-meter and the chart told them I needed a 143mm wide saddle. That has really worked for me.

Of course, Brooks is a whole different ball game. I think because of the differences in the way a Brooks saddle is constructed the width of a Brooks saddle means something different than the width of a typical plastic-ish saddle.