I go to various websites' Returned merchandise" and "Closeout" pages and buy $10 and $20 saddles,. I look for saddles (if they say anything) which say they are for riders who stay stationary on the seat by and large, because that is my riding style. I try different saddles and keep the ones I like. If I lived near a Performance Bike store, I wouldn't have to buy them first, which would be nice.

That Cervelo page linked above is pretty good. The basics I got from it is that you should determine if you are wide-bottomed or narrow. I have saddles with different stated "widths" that work the same despite their stated differences ... not sure how the companies measure. overall width is one way, but how about supported width? Anyway .... unless you are really wide or really narrow, hit-or-miss might be your only option.

I am a Clydesdale, and never found saddle flex to be a big issue. Don't buy a saddle at Wal-Mart and you should be fine with that.

If you need the seat all the way forward, is that because your bike frame is too large? Reach too long? Hard to find a comfortable saddle if the rest of the bike isn't set up right, because you won't get good weight distribution.

Sorry I cannot really help, but you have enough knowledge to make the right choice already. Fare well with your venture.