Of the two tractors you have narrowed down to my choice would be the Kubota B7610. It is an established design that has been on the market for a few years and proved to be a pretty trouble free unit. Take a look in the Kubota forums and you will not see many problems posted about the 7610 and it is a very popular small tractor. The Kubota has slightly more 3 point capacity than the Deere.
The Deere has a loader design that is more modern, with a slight curve to the loader to increase visibility. This is a very marginal improvement over the Kubota's design. The Deere has a longer wheel base and a little more weight, that may help a bit with ground engaging tasks, and the added wheelbase may be a slight bit smoother ride, but the reality is both of these are small frame tractors and capable of basically the same tasks.
Do youself a favor and ask yourself if you'd rather own one or the other. Pick the one you prefer and you'll probably be pretty darn happy for the next 10 to 20 years.