I'm looking to replace 2012 JD x540. The Kubota GR2020 and the all wheel steer JD x584 have both sparked my interest. We mow up to 2 acres of hilly and flat mixture land. Lots of bushes, etc. Snow blow during winter. Can someone tell me if there are problems with the new GR2020 compared to x584? Also, Can forward speed on GR202 be adjusted? I mow slow, but need to haul stuff 1/2 mile away on a road. Thanks for any help.