</font><font color="blue" class="small">( How is the BX better at mowing than the higher HP
B7610? Does it have a better MMM? )</font>
I believe it has to do with the way the mower deck is attached to the tractor. On the Sub compacts like the BX, TZ, etc., the deck floats off the frame of the machine like a garden tractor or lawn mower. On the larger compacts, the mower deck actually rolls along on the ground, so it follows the contours (dips, high spots, etc.) more, so you may not always get as nice a cut on your lawn with a compact as you would with a sub compact. A floating mower deck gives a more even appearance, without showing every little dip, hole, etc.
However, for that acreage, if you think you'll end up doing a lot of landscaping on your property, I think it would be good to look at a compact machine instead of a subcompact. It's all about ground clearance. A sub will do fine for work on a manicured lot. If you have a lot of dirt work, land clearing, tree felling to do on your property to get it to the manicured point, the added ground clearance of a compact will be a big benefit. And a compact will still do a decent enough job at mowing that most folks really wouldn't notice a difference.