I have a Scott's 16hp mower. It's WAY under powered. It bogs down easily and I can just forget about mowing if the grass is the least bit damp. I also purchased the bagger and clogs consistently. Unless it's in the dead of summer and hasn't rained in week, the bagger clogs with just the moisture from the grass.
Now for the good news. The Kohler has never failed me in 2 years and the deck heigth adjustment is a breeze.
I'll never buy another riding mower with less than a 20hp. It's worth the extra money.