I've done the ass-O-meter, and while interesting, it didn't provide an accurate result. I've also ridden stuff that worked great for many other people but me.
What I suggest is you patronize a store with a generous return policy and keep on trying them.
Competitive Cyclist even has a program where they ship you a whole box of 'em.
Also, no saddle, no matter how perfect for you, will deliver the goods if it isn't adjusted correctly and on a properly fitted bike.