Scott

I flew my first 2.4 unit an AR 7000 back in November 2006 using a Professional unit with 2 x 4.8v Nicad batteries.
If anything a powerbox system should be better because of the dual batteries and stable voltage.
You won't have a problem.
The stickers on boxes were only done because people kept asking whether it would be OK.
No difference between early and later units as far as 2.4 goes.

Dave Wilshere