The ones I have access to are 208v and they are well worth the money. You can blind people with them if improperly used, so make sure to hang and program them properly. Colors are ok, but I think a little too "cute" I prefer just plain white.
I have only used Dataflash AF1000's, but they are very similar to the Atomics. Yes, they are really bright and work very well. Watch out for the heat/lamp timeout.
I've used an Atomic 3K in various settings, it's an awesome strobe light. Very bright, and many different settings/modes. I've never used the scroller, but I have put gels in front of it... I prefer the white.