I have 2 30+years old Kubota utility tractors. Trouble free except for a hydraulic pump some years ago. I'm sold on the company and I'm looking at a Z turn mower now. I have 6 acres, with some steep hills so the 4X will still be used. My question pertains to the engines available. There is a 27 hp Kubota gas a/c twin, for about 10k. 3 w/c, 2 diesel and one gas for around 13k. What does anyone know about the Kubota a/c twin and the 3 cyl. gas. I know the diesels are bullet proof but don't know much about the other 2. This would compliment my tractors so don't know if I need the diesels for the extra 3 grand. Back before the Kubotas I would replace air cooled twin engines every 3 years and gave up on them for the diesels. Thanks all.