The newer Gen X line (Natural, Elite, Presitge) that came out in 2010 are either regular or forward but the in previous production years them made the Gen X Traditional (or sometimes called "Classic"...I think) with a long flap. A boarder at my barn (adult mind you) had a heck of time finding a saddle that would accomodate her long thigh and trying saddles with larger seats and/or with forward flaps did not suit her. Just on a chance the tack shop owner said why not try the Gen X with long flap and "bingo" it did the trick. I've ridden in it myself and it's very comfortable and I love how centered and secure it makes me feel that I am selling my Bates CC to buy one myself but with a regular flap. I liked my Bates very much and the seat was very comfortable but was always pitching forward (thought it was me) but when I started using the Gen X the problem went away and could SIT THE TROT too without bouncing all over the place. It was just a fluke that I ended up trying it out and it worked. See if you can get a demo to test ride in. Below are some retailers that carry the Gen X with the long flap.
My Childeric model M with a forward flap did the trick for me. My prestige was just a hair too small in the flap, I think it was just a regular flap. but if the prestige had a forward flap I think it would have worked for me.
You can find those saddles used in the $2000 range.