Had three of these installed a couple days ago to replace the toilets that were installed by the builder when the house was built.  The original builder installed toilets were having issues with incomplete flushing and sometimes would find water droplets on the toilet seat.  I purchased three of the Koehler model Wellworth K-3977 from a local plumbing company and had them professionally installed.  I am very happy with the flushing performance and no more water droplets on the toilet seat.  This model does not come standard with a toilet seat so you will need to take that into account.