I think the only thing that is kept from the original seat is the pan. The foam doesn't feel like what was original. Its firmer feeling. I ordered mine with color matched Kanjis' on the front seat. Cool touch they offer.
You send in your seat to Tobin. They have you fill out a questionaire for specifics to build on. In my case they actually had to do my seat twice. Tobin (his actual name), said he had never done a seat for anyone my height. The first attempt left me sitting on the new riser rather than the pan of the seat. To rememdy that I sent it back and he angled the riser back which fit super comfy after that. Yes the rear passenger seat getting a riser is a HUGE help for the passenger. They don't slide all over, which distracts the driver as well. The only downside to Tobin is, they are swamped with work. It takes them some time to return calls. Worth the wait however.