Bill
FWIW I own a 4230 that I bought for haying and hauling hay. I really like it. I paid $12000 CDN three years ago, but it looks rough, but Mechanically it is pretty sound. Mine is a very early model, 73 production and has 10,000 hours on the clock. I replaced the original seat with a personal posture seat out of a '40 series. It bolts right up to the existing suspension. Since everything else on the place has pioneer couplers, I replaced the barrels in the couplers with the conversion kits available from Deere. I have heard some people have problems with these kits, but I have had no problems so far.
Pros.
It was as relatively cheap. Love the Quad range for baling. Shift up and down if the windrow gets heavy or thin. Has plenty of power to run a NH664 baler. Good hydraulics. VERY comfortable to ride in. All controls are placed where it is easy to use and natural to find. New seat is WAY more comfortable than the original. Cab is not as quiet as our 2755, but is still reasonably quiet. IT is MUCH quieter than cabs from other makes of the same age. If you find it too loud I have come across some discussions on the 'net on making the cabs quieter using components and concepts from later series cabs.
Hooking the bale alarm from my baler was a piece of cake. There is an electrical circuit breaker under the cowl in the cab that you can hook a wire to which makes the monitor shut off when the ignition key is turned off.
If you wanted to put a loader on it, the front end is built heavy and should take the abuse of carrying round bales. There is enough iron there to handle a bale on a loader without too much need for added weight.
Parts support is great from Mother Deere and after market sources. Also there are a lot of mechanics out there with a experience with these tractors. This tractor is 30 years old. Things are going to break and wear out.
Cons
It is rather cold blooded to start. Fine in the summer, but when the temps drop in the '40's a short time with a block heater will make a big difference. Batteries and cables make a big difference in cranking speed and thus starting. Mine has 00 cables and has two 12 volt batteries in parallel rather than the factory set up of two 6 volts in series to produce 12 volts. I have started mine in sub zero weather with no assistance, but it was not something I would recommend all the time.
Fuel consumption is not as good as some tractors in this size range. Some people have unreal expectations when it come to fuel consumption. If you are asking a tractor to put out 100 Hp, it will not burn 1 gallon an hour. If fuel economy is a real issue, look at a 4 cylinder diesel with a turbo, like our 2755. The 2755 is a good tractor, but when it comes to heavy duty jobs, the engine delivers, but there is not enough iron there and it gets pushed around.
The AC is not as good as later series Deeres. If there are problems a good AC man should be able to get it to cool adequately.
IF you have time and a little more money a 4040 is just a slightly updated 4230. Better cab and AC, I've been told. For me, my 4230 has been a lot of bang for my buck and I am glad I bought it.
John