Skip,
I would go with the full floating combination, mainly because the axle is only carrying a torque load and not required to carry the weight of your car which may get pretty heavy. Coleman Racing has some pretty nice units for IMCA racing that are not overly huge, I just put a set on the new QC for my little street rod.
Now if cost were not a constraining factor I would design and built a set up using preloaded angular contact ball bearings. Lower rolling resistance and still good radial and thrust load capabilities and if you were really bucks up you could probably use ceramic bearings too! plus they would have a labyrinth style seal for no seal drag. $$$$$
Rex