Setosa IS a branching and encrusting montipora. If your setosa never branches I would question if its a setosa at all.
http://coral.aims.gov.au/speciesPage...ata/0529/view#
That said the frag on the right looks like digitata...some on the left look to be setosa...but yes a bit branch(ier) than most I've seen. Probably a flow thing.