I recently watched Series 1 over here in Blighty and yes I think it has potential.

I don't know which direction S2 has taken it, however.

I have yet to get Con X V2, but I wonder whether it would make a better foundation, at least for a PCs-as-investigators-of-the-4400 type of game.

Granted the powers of the 4400 could be covered by the Angel RPG and a game based along those lines could be good. Any thoughts on who the adversaries would be?