I use the 54" standard cut deck. It cuts really nice and discharges very well.
I can mow 4" to 5" deep grass, relatively thick to a height of 2" at full speed, high range, at 3000 rpm with out any clogging. At that speed taller things like daisys etc will stand back up, but no complaints. Also I mow without loader or backhoe. The only drawback I see to mowing with the 24 is under trees. The wide ROPS sucks. Even folded it grabs anything it can. Other than that it is very nimble. I mow with R-4 tires and do not dig up the lawn.