You didn't mention what you want to use your tractor for. I have a
B7300, which is almost the
B7500 (no power steering /forums/images/graemlins/frown.gif and a couple less HP). I'm on 10 acres and would have probably been better off with a larger tractor. But I'm really happy with it - I don't know what I'd do without it.
I use mine for brush hogging about 6 acres of pasture, knocking down and dragging dead trees, backhoe work, and of course, taking the trash can up and down the driveway. I maintain the drives with it, too.
Get an FEL - it is really handy, and you'll be surprised how much you use it. Float control would be nice. The
B7500 has power steering, so that gets rid of one of the few complaints I have about mine. Airflow is bad - the darn screens clog up in no time when you have fuzzy stuff floating around and then the tractor will overheat. Another issue with these tractors is that they don't have a real alternator - they use a low power dynamo which limits the electrical accessories (lights) that you can add.
But they are great machines and you should be pretty happy with either choice. I'm of the "get the bigger one" school, but if you need to get your tractor into small places the smaller one might be the better choice.