My GR2100 worked great for the first 100 hours, and was meticulously serviced. When I changed the fluid in the front axle, I noticed a lot of silver "glitter" in the old oil.
Soon afterwards, I found the machine sitting in a pool of oil that had escaped from the right rear axle seal. The eventual fix was a new case from the dealer, which, thankfully, Kubota covered. It took the dealers mechanic two shots to get it done correctly.
Following this issue, the drive shaft from the rear axle to the front came apart. It is poorly supported and held together by a "c" clip. I don't know if these issues are fixed on new machines, but they are not acceptable.