I have a Simplicity ZT-2500 (front suspension only) with a Briggs Commercial 24hp engine on it along with a 48" fab deck. It cost me $3300 about 5 years ago. It has ZT2800 transmissions with the spin off oil filter (I've replaced them twice now and changed the fluid in there three times). I have not had any issues with the transmissions but I will say since I also have a Simplicity ZTR with ZT3400 transmissions that the bigger ones are better than even the 2800's for power and response and just all around speed (11mph) cutting grass. It does have a 27hp Briggs Commercial engine which delivers more power but if it were me I'd buy the bigger transmission first.