if you have reasonable access to the plumbing, this might be a good time to fix your rough-in. You will have a much easier time finding 12" offset toilets in styles you like, at prices you like, etc, and if the bathroom is small, you should end up with more legroom this way than with a 14" offset toilet.
between the two toilets, just by quality, i'd def go with the toto. kohler is a bit spotty, toto is much more consistently solid. Sounds like the space issue is better with the toto as well, though I don't know anything about that personally.