Durability of the front end, loader frame, etc, is actually a bigger issue with a 2wd than a 4wd. One might think that a 4wd would cause higher stress on these components, but, because a 2wd operator often has to use momentum to assist in getting a full bucket, while a 4wd operator can just power into a pile smoothly and without loosing traction, the reverse is true. Even a novice has to try real hard to damage a 4wd loader, while a pro can wreck a 2wd in short order if he is under the gun to get a job done. Broken welds, etc are much more common on 2wd loader frames for this reason. The only way a 2wd tractor is effective on a loader is if it carries a very heavy load on the rear axle, and that will cause issues with trailerability, soil compaction, tire longevity, fuel consumption, and overall stress on the machine. Also, as already mentioned, 4wd will cost you some more up front but you will make that up and then some on resale of any loader tractor. If you are one of the few who can get away with a 2wd loader tractor then I would strongly reccommend going with a used machine so you dont get hit with the massive depreciation that you would absorb if you buy a new one. Used 2wd loader tractors are selling today for pennies on the dollar, while you got to look real hard to find a "bargain" 4wd.