I had a diesel X740 for years, and loved it - until the problem. It was everything I needed (as I had a 4WD diesel 650 with a snowblower and 3 point mower as well.
The X740 engine and transmission were excellent. I had constant nuisance electrical problems, including starting. I always got it going again, but sometimes it was tiresome. It was a little too computerized to diagnose simply. The problem was that it caught fire in the middle of the night. Sadly, when it did that, it was in my airplane hangar with the airplane, the JD650, my Polaris 6X6, and my workshop. I had good insurance, but would really rather have not had the problem in the first place.
So, my advise is to maintain the electrical system to perfection, have any problems promptly and properly repaired, and consider disconnecting the battery if in any doubt.
I bough the 1025R to replace both tractors, and it is fine. I would happily have another X740 for lighter work, but I'd always have a sideways glace at the electrical system....