I voted for the springer seat. Advantage - much more comfortable ride, disadvantage - even though I am fairly small in stature and do not have the "extended abdomen" of those in my age group, the seating is too high and too far forward for comfort. When I drove M35s for he military (N/A LD427s I guess, I was too young and too inattentive to care) we had the box seat. They were positioned better for driving comfort, my butt was sufficiently hardened at the time that it did not bother me. Did not make much use of the under seat storage either. Later in the fire service, some of our newer vehicles had adjustable air ride seats. Talk about an amusement park ride! Those things were a real trip, most of our service area was rutted graveled roads, we were constantly bouncing around. I guess they'd be OK on paved roads, but really sucked on the rough roads!