Hi! Just thought I'd let you know that both Kubotas are excellent! I have a ZD-18 Kubota(the ZD-21 has larger tires,60" Deck,21hp), the ground speed of either a BX or ZD does affect cut quality(slower the higher the quality of the cut). If I remember right you have 2 acres to do. Speed won't matter much with a 54" or 60" Deck you'll be done in no time! The ZD only mows(its real heavy in the back,that's why no factory hitch,could tip backwards)ZTRs are hard on the lawn in turns if not careful,but if you have long flat straitway of a lawn,plus lots of trimming they are the hot ticket. One note is are you the only one that will run the Kubota? If someone else uses the Kubota are not familiar with ZTRs it can be trouble! BX is easy for just about anyone quite fast, and can do just about anything! Oh,think about trade-in or resale time to, in your area are comm. mowing co. useing ZTR or Tractor,could make a difference at that time. It's a tough call to finalize any choice, I made mine like this. 1. SPEED(ZD),2. PRICE(ZD),3.COMFORT(ZD),4.AGILITY(ZD),5.FUN(ZD). If I was making a list for BX, 1.DO EVERYTHING(BX),2.FRAME THICKNESS(BX),3.EASIER TO TALK ANYONE TO BUY(BX),4.COULD BLOW SNOW IF NEEDED(BX),5.FUN JUST IN MORE POSSIBLE WAYS(BX). Thanks for ZD/BX talk! Andy.