What many people discover with pressure assist is: they require more maintenance, they're loud, they often shred things, and leave little bits in the tank, and they don't necessarily flush any better than a well-designed modern gravity toilet. So, you can buy one if you wish...good luck to you. It was an idea to overcome poor engineering and use old molds and products with the smaller quantity of water required by the feds.
Terry has some comparison tests of various toilets. Most of the Totos work quite well, and the newest ones only use 1.28 gallons/flush. Some of the Totos are a little unique in that they use an adapter to mate the toilet with the flange. This allows them to use the same toilet in any of the three standard flange offsets: 10, 12, and 14". So, you get the same exact toilet, but use the adapter required to get it to sit where you want it. I've got 2 Totos that use this adapter, and they work fine. I've put in two Dalton model Totos at my mother's house, and they also work great.