I have owned only a B7800 and that only since March '05 so I can't rate against other machines. However, I can't imagine that your tractor needs will require more machine than the B7800. I have 130 acres (mostly wooded) to maintain and a mile long gravel drive and the B7800 has done all I've asked. The big tasks I've done have taken longer and required better planning than if I had a heavier tractor but I'm retired so time is all mine. I covered some heavily wooded, hilly areas yesterday and couldn't have moved a bigger machine around. The B7800 handled clearing the path as well as being stable on the hills and in the ditches. Of course, I'd probably be saying the same if I had a bigger machine but then I'm not looking for a way to enjoy less tractor time.
L3400:
I was just where you were at 3 weeks ago had the 7800 ready to buy. The great advice I got here led me to L3400
and I am sure glad I did not much more $ but lots more tractor. For manuveradilty it gets where ever you want to go.
Just the weight for moving trees and bushes was worth every penny. We are building motocross jumps and it also digs dirt great.
I own a B7800 since last year and I like it a lot. /forums/images/graemlins/grin.gif
If you need a small light tractor then the B7800 is a good choice. The B7800 tips over very easy though. Go for an L-series tractor if weight is not a problem.