I looked at both too, and ended up with the Kubota, mostly because it was available, and I needed something right then. Though it isn't important with the implements you are going to get initially, I really wish mine had position control on the 3 pt like the JD. I grew up using small tractors with steering brakes too, and I wish they were easier to use on my Kubota. In mud, snow, and sometimes when backdragging with the loader, etc. they are really handy. I do like the three range transmision on mine, fewer things hanging off the bottom, and the overall build quality. I have a QA on my loader, so that is a wash. I think the steering geometry on the JD is a little better for finish mowing since the tires seem to "lean" into the turn more, and seem less likely to tear the turf with the outside of the outside front tire. You can't really go wrong with either. It used to be that the implements like snowblowers, front blades, etc. were better matched on the Kubota, and that influenced my decision too, but I see that JD is addressing that.
Try them both, think about what things are most important to you, and have fun shopping!