Purchased the JD 425 all wheel steer in 1999 and have used it for mowing 3 acres and plowing snow from a 1/4 mile drive since that time. 54 inch mower deck and 54 inch snow blade.
In that time, I've been consistently pleased with mowing performance (very versatile; follows the contours of a not-so-level lawn very well) and snow plowing.
However, some body parts are not as well constructed as they might be. For example, the tail lights came loose within a few years and have basically been just hanging on ever since. Also, I had to have the engine rebuilt after 600 hours due to burnt valves, and lately the transaxle has developed a leak.
While the tractor has got the job done on a large yard and very long driveway for 15 years now, it hasn't been inexpensive either as an initial purchase or to maintain. For general durability and doing a nice job, I'd buy the same model if I had it to do over again, but I'd be much more satisfied with my purchase if expensive repairs didn't crop up every year or two.
In fairness, the first 7 or 8 years of service almost no additional expense was necessary. But the last 7 or 8 years I've paid approximately $3K to my JD dealer to keep the 425 operational.