There is not much out there that will out cut a Tiger Cat Scag especially if you have taller stemmed grass. The Velocity deck is incredible. We cut incredible amounts of grass in Lower Alabama with them. All four of the mowers we have are Tiger Cats with 52" decks and 22 HP Kawasaki engines. I have one that has over 1800 hours on it. I have seen several Kawasaki engines that had lots of hours on them with little to no problems. I can't say that for the Kohlers. I personally have not seen one with 1000 hours on it that was not using a lot of oil or worse.
I went with the 52" decks for several reasons but for some unknown reason it appears that they cut tall stemmed grass slightly better than the 61" decks do. Neither is anything to sneeze at. I used to run Kubota mowers but the Scags for me are shockingly better.