This toilet looks very sleek and modern. It has powerful flushing with little water. It is a great toilet by design and function, but unfortunately, porcelain coating quality drags down the rating.
I bought four toilets. Two are fine and two have imperfect porcelain coating. One has a small grey spot on top of bowl, oh well, I decided to keep it. The other has two long grey hairlines on top of bowl, too obvious to ignore and I decided to exchange. One lid has uneven coating and looks weird. For a toilet with price tag @$300, this is unacceptable. Kohler should 1) improve porcelain coating process, and 2) rinse off dust/debris before reaching their quality control, so the ones with cosmetic deficiency can be caught.
I am very happy with Kohler customer service and Home Depot customer service. Both are very responsive. Home Depot customer support scheduled a shipping company to pick up the bad one from my house, and placed a replacement toilet to deliver to my house in two days. Therefore, I still recommend this toilet - do check your new toilet thoroughly right after delivery.