I always used a full 10 foot stick of rigid metal conduit where I came out of the slab. Reason one: at least five feet of metal gives a lot of strength to the sweep. Reason 2: 3-5 feet of riser is noticed, and gives me a chance to straighten the pipe easily if it needs tweaking when it comes time to finish the run.
As far as bonding the conduit, I would depend on the locknuts in the box for the bond.
