Could someone comment on the Toro Z580-D with regard to the 23 HP Kubota Diesel? It is now sold with a 25 HP Kubota but I am considering buying a previous year demo (22 hrs) with the 23 HP for my farm cutting 10-12 acres. Is the 23 HP diesel underpowered for a 60 inch deck? After doing a search here I couldn't find much info. Also, the price is a little over $9000 so it's at a nice discount. Thanks.