Di/Bipolar speakers would be a superior choice in a strictly 2 channel or 2.1 system. Implented well they can really contribute to imaging, ambience and spaciousness. Most of us however are now using our rigs for 5.1 or 7.1 systems. Whereas I would strongly consider bipoles/dipoles as surrounds in a 5.1 system, I'll stick with high quality (very) wide dispersion direct radiators for 7.1 ... I'd want all loudspeakers very closely tonally matched, and if possible to be identical. Following implementation of proper diffusion treatment in the room, "monkey coffins" are indeed the ones with most promise for 7.1 setups.
Tumara Baap