I have a B7800 and use a Bush Hog 72" finish mower for my yard. The tractor hardly notices that it is there. When I lift up the mower the front gets light with no loader on so extra weight would be nice. I don't do much heavy loader work so I have no need for a larger machine but the L series is sure nice. It comes down to what you would prefer. If your current machine is closer in size to the L series and it is just fine for the work you are doing then there is no contest. If you feel it could be a little smaller at times then consider the B. From your description it sound like either work.