As far as 8' bed is concerned it is a matter of personal preference. The longer bed rides smoother when empty, adds storage space, and precludes any possibility of the corner of the trailer striking the cab in sharp turns. The standard 6 1/2' works just fine for many, it is more maneuverable and easier to park. Trailer to cab interference can be an issue although many trailers have the front corner recessed to prevent collisions. If it is a problem pin box extensions and slider hitches are available. With our crew cab we much prefer the standard box in mall parking lots.