Hmm, very nice. I especially like the strong outlines on the helmets; they're a bit cartoony, yet cool-looking. Well done paint job, too, Sev looks particularly succeeded.
However, I have to say I don't really like the visor of Scorch. It's rather dark and unclean-looking, while the others - particularly the ones of Sev and Boss - are neatly bright and of a really good-looking shade of blue.
Good job, overall, though.