I have a 4300, and have no negative things to report. Some early problems with front axles, for users wanting to turn on turf. If a problem, new axles were switched out and replaced by Deere at no cost. The original axles had some advantages over the replacements, but it depended on the uses of the tractor.
Some have had problems with the instrument panel fogging over, but that has been a problem across many of the other brands as well. Deere fixed that problem on mine.
Some reports of leaking batteries, and Deere fixed the problem. Also similar reports are found of other brands with the problem.
Some have found the transmission steel mesh oil filter with plenty of filtered out metal particles. I did too, but there was still plenty of filter space left to filter out more. Recommendation that the first filter and hyd. oil in the transmission be done at around the first 50 hours, and then follow the manual after that.
It is a good tractor, IMO. Dealer said the resale of these mid-size 4000 series is unexpectedly high now. Maybe it is the history of them.
I am considering trading up to the 3520 (just because I think I like it better) but am nervous about letting my faithful 4300 go at the same time. I have about the same # of hours (around 230) so its probably not broke in yet. /forums/images/graemlins/wink.gif