I have a Tillet XL standard flex that is too big. I just tried sitting in the same seat in a Large-medium. It seemed to fit okay but with my Tillet L ribvest, I pivot laterally in the seat. Without the vest I don’t. If I push against my feet I sit more upright (with the seat flat) and then it seems better. I tried tilting the seat back and this felt more natural. I thought this was a slam-dunk getting the most popular seat in the right size. How important is comfort? Is a rib vest really useful at LO206 speeds? Are there other seats racers can suggest I try? Thanks.