Shooting "Studio Booth" at Conference with D700 - Help!!

Wow, I can't thank you enough for your time!

I talked to the guys at lensrentals.  They recommended their Profoto Air D1 500/500 Twin Monolite Kit, which granted is the most expensive kit, but it seems the peace of mind may be worthwhile.  With shipping it'll be $200.  They said I should have no problems plugging straight into the wall.

What are your thoughts on that kit?  Will I need anything else?  Would you see any risk with shooting handheld at 1/250th?  With the wireless transmitter that comes with the D1 kit, I can technically go faster than that, correct?

Thanks again!!