This is more common in the world of big trucks, where there is concern for steering geometry (and the ability to make sharp turns), weight distribution, and ride quality. A longer wheelbase (common with the Set Forward Axle) has a wider turn radius (assuming the same steering angles otherwise), but will experience less "bobbing" and "Nosedive" when braking.
Even with a full length bus, I doubt you'll be visiting many narrow residential streets so the turning radius won't be much of an issue while on the road. Your storage arrangement is another matter. I know mine was, which was why I needed a shorter bus. The SFA will give you a little more distance between the axles, which is good for all the "basement" stuff you may wish to add.
For our purposes, I don't think there is much practical difference between the SFA and SBA - maybe a foot or 2 of wheelbase length for an otherwise identical length bus. The SBA would be somewhat easier to navigate through congested city streets and tight turns with its shorter wheelbase.
