I ordered this knowing it wasn't quite a standard toilet, but unfortunately the minimal amount of information available on the Kohler website didn't make it clear how different this was.
First, the things that come up on the spec sheet that you may not notice looking at pictures:
(1) this model has what's called a full-skirt trap - the sides of the toilet are completely flat, which means it does not use standard bolts for attachment.
(2) this model is actually considered a "compact elongated", which I had no idea existed. It's only 27-3/4" deep, making it about 2" smaller from front to back than most toilets. This could be good or bad depending on your situation. In my situation, where a door swings close to the toilet, this was good.
Now, here's where things get tricky:
(1) the full skirt means that this toilet uses a completely different trap and mounting system. A plastic trap insert actually bolts to the floor, and the toilet bolts to the trap insert. Nowhere on the Kohler website is this actually explained, so I'm including photos to make clear how this actually works.
(2) depending on your floor situation, this system may not work. I have tile that raises floor level well above the flange. My plumber refused to install this toilet, saying there was no way to get a tight fit. He said it will only work where the floor and flange are on the same level (i.e., no tile or other flooring added after the fact). He said a wax ring could not be used to bridge a gap - the plastic trap has to be inserted into the flange. Maybe he was wrong, but all I know is that my old malfunctioning toilet is back where it started.
So, in the end, I couldn't even test out this toilet. I was a little surprised at the cost, and from examining it, I can't quite figure out why it's so expensive. In fact, I was shocked that it came with a plastic toilet seat rather than a wood one. The toilet also emitted a sort of hollow ding when tapped, which made it feel a bit cheap and less than solid, although at a very heavy 115lb., it is clearly not not a lightweight.
Difficult to Install