Both the L & B series are avail with gear or hst trannies.
Mid PTO standard on B, and optional on L and Grand L. Kubota's web site DID list a front snowblower for the L series a while back. They do have the front blower listed for the Grand L.
L series weighs considerably more than the B. (~900 lbs + more) Grand L weigh even more, and are larger frame tractors also.
More weight, larger, heavier implements, larger tires, larger physical tractor are in the L's corner.
Lighter weight, smaller implements, more maneuverable are in the B's corner.
Some B series (7510/7610/7800 are "basic" tractors. Some (2630,3030 are "deluxe" tractors. All L series are "basic" tractors. All Grand L series are "deluxe" tractors.
Some "Basic" tractors lack position control on 3pt (at least on the B series), telescoping arms on 3pt to make hook-ups easier, sometimes lack the stronger pumps (hydro & PS) of deluxe tractors, have more simple seats (translation ... less comfortable) etc.
B series tractors are design for: Mowing large areas (in field and near house), light brush clearing, light - medium landscaping chores. Snow clearing.
L series are better equipped for: Mowing large (not so smooth) areas (ungraded fields), medium brush clearing, medium landscaping chores, snow clearing (heavier, faster snow removal)
Grand L Mowing fields with larger (7 ft+) mowers, heavy brush clearing, larger landscaping chores etc.
They are really 3 different types of tractor (B,L, Grand L) If the 7880 and 2800 look similar on paper, I suggest you go to your local dealer and look at them in person. You will see 2 totally different machines.
