I appreciate Mike's kind words. I have owned a 4310, two 3720's and a 4520. I can say each has its place, as would a 990. The big question will ultimately surround your budget. If you want a powerful, simple tractor that will last a long time but is really basic, a 990 is for you. The performance and comfort of the 3720 and 4000 series machines is in a different league entirely. Of all the tractors I have owned, the 4520 was my favorite overall. It was big, stable and had a nice loader. Even though I loved the 4520 I think the 3720 is a better choice all-around for most of us in the compact market. It has tremendous power, much more than most of us have seen before, is small enough to manuver and access tight places, but large enough to lift heavy things with the loader and pull heavy implements. To me, it is about the perfect size. My neighbor has a 4320, and he works it to death. I have used his machine some, and although it lacks the pep of my previous 4520 or my current 3720, it is a really nice machine and still has quite a lot of power. I am a big supporter of the ehydro tranny and I think I would favor that if looking in these lines. My advice is to price a 4120, 4320 and 3720 with hydro and see how they compare to the 990 in price. If the prices are close, go with the 3000 or 4000 machine. Either would do the job. Spending extra money now, if possible, would not likely be regretted later. Also, resale value and market is important. You might keep whichever tractor you get forever, or you might not. I tend to use and trade often, and a 990 has to be marketed to just the right person, who wants a simple no frills machine and one who would not mind the collar shift. The 3000 and 4000 machines appeal to almost everyone. They drive like cars, are built like tanks and would last about two days for sale most places if you ever found your needs changing, so I think in general they are a better equipment investment.
John M