Remember that just because the gullet is changeable, that does not mean the saddle will fit your horse. My step-father, in an act of, er, kindness, went ahead and bought me a brand new Wintec 2000 AP saddle, as well as a gullet kit. He thought that because I could adjust the gullet, and the CAIR system was within, I could "make" it fit. It does not fit at all. It pitches me forward, forces me into a bad position, and, in addition, it's terrible on Mudpie. I've done extensive measuring, adjusting etc, but it just doesn't work.
I'm definitely not saying that Wintecs won't work for people, because I'm certain there are people out there who have had good experiences with them. But as it is right now, I am not one of them. Just letting you know!
It may be a good idea to just do some saddle shopping, and have a professional help you fit a saddle. With SmartPak, when you do test rides on saddles, they pay shipping both ways. :)