I was in your almost exact situation about a year ago. I started out looking at a
BX2230 and a few months later I ended up with a
B7800 w/ loader, mid-mount mower, box blade and rake. More powerful, heavier but not too heavy to mow with, bigger tires, etc... I have five acres, half cleared half treed and I would say the
B7800 is almost perfect but in reality a
B7510 probably would have been perfectly adequate. I had some kind of heavy work to do at first and the extra power and small weight advantage of the
B7800 sold me on it. However, now that I have grass and am doing a lot more mowing the
B7510 would probably be a better fit for me. I do think that it would be very smart to strongly consider the
B7510 over a BX - you gain so much more in terms of capability and in terms of implements you can use. Anyway, to answer your more specific questions:
1) The FEL is extremely easy to take on and off once you do it once. If I was racing I could probably have it off in about two minutes and back on in about three or four. Just make sure you always do it on level ground. /forums/images/graemlins/grin.gif
2) The mmm is a different story. Although not incredibly difficult it does take some effort. It usually takes me about ten minutes to put it on and maybe half of that to take it off. The problem is that you don't want the deck on when you are doing anything on a surface that isn't level. For me this means I pretty much have to take the mower deck off anytime I want to do any other work and put it back on when I want to mow the lawn. This inconvenience would not make me second guess my tractor choices but it is something to think about. Unless you are going to get a rear finish mower or a seperate dedicated mower I think you would have this issue with any tractor you get. You may want to consider using the $$$$$$$$$$$$$$$$$$$$$$$$$$$ you'd spend on the mmm and get a decent rider mower instead. If you do go with the mmm just make sure everything is set up exactly as shown in the maual. My front link arm was a little off when I got it and it made it incredibly difficult to get the deck back on after I took it off the first time.
3. As far as the box blade versus rear blade, I have never used a rear blade but I do use my box blade extensively. In my opinion the box blade is almost as necessary as the FEL if you are going to be doing any grading/material moving work. I am however going to get a rear blade in the next few weeks to plow snow with and it will be nice to have for a couple of other things that the box blade isn't ideal for. I would buy whichever one sounds like it will be most useful to you now and then you could keep your eyes open for a cheap used one of the other. I see used blades in the paper all the time around here but they are always sold by the time I call on them. /forums/images/graemlins/mad.gif
4. As far as used versus new (wasn't one of your questions but I'll answer it anyway), around here a used tractor in good condition isn't much cheaper than a comparable new tractor. If you can find a good price on a used one I'd say go for it if it is in good condition. However, I think that Kubota still has 0% interest for two years going on through the end of the year so if you aren't opposed to financing you could take advantage of that. Then you get a nice new pretty tractor that you know hasn't been abused. Just my opinion.
Hope I helped you out a little here.
Matt