I building one for my Toyota. I went with it because i have basically no money invested in it. Parts are really no more expensive for it, and you can get anything you want ( lockers, truss, disc brakes, ect, ect)
Also, like Bones said, they have good ground clearance....my stock housing is less than a quarter inch longer from axle center line to lowest point than my buddy's 14 bolt that has been cut all to hell with Ballistics shave kit.
As for narrowing it....they use two different length shafts stock....you may be able to retube it to use two of the shorter shafts to narrow it while still using stock parts.....it won't make it a lot narrower but it will some
09 Dodge 2500 w/ a Cummins, dd/towrig
85 Toyota Pickup, 1tons, coilovers, 40's, ect