I have already done an Aurora figure. When I tried to do the same for Northstar I ran into troubles with the material. They were sculpted in mirroring poses, but sculpted with different costumes. I tried to remove the wrist bands, but due to the rubbery nature of the material I wasn't able to do so. He ended up becoming a custom character named Zyklon, who has paired up with Kriegshunde to battle the Exiles on at least one occasion.
New versions of the twins were released in the Guardians set, again sporting mirrored poses. (Looking a little too much like the Wonder Twins for my taste, but whatever.) I rebased them and did some quick touch-ups.
The skin got a light coat of GW Sepia wash. The white was touched up with GW Skull White with no shading. The black parts of their costumes were touched up with P3 Thamar Black and then dry brushed with P3 Coal Black to give it a little bit of depth.
I'm tempted to go back and try doing another version of Northstar using the original figure sculpt, simply because I like that model a lot better. In the meantime I've just got to finish Vindicator and Talisman up to finish the team. Once they're done I'll post a few shots of the full group of figures. The it'll be on to a version of "The Master" and some form of Omega Flight.