Basically they are the same thing with one small exception. On the 'halo' or angel eye, or whatever, around the projector orifice where the bulb goes is a luminescent ring to give the housing a 5-series look.
Technically the new Halos are not projectors. The Nis-Knacks projectors had an ion lens much like the HID projector in the S14B headlights. This is what makes them a projector. The Halos are projector-like, but only really have two circular light housings. If you can get your hands on a set of Nis-Knacks projectors, I would - I like 'em better.