TOTO makes a number of models that use a "unifit" adapter that will accomodate 10, 12 or 14 inch RIs with the same toilet, but you do have to buy the 10 or 14 in adapter (about an extra $50, I think).
It is a slick setup, very easy to install and as most Toto users on this site will tell you, Toto's are second to none operationally. A little more money than the Home Depot specials, but well worth the money.