the millenium pro has a built in pit wizard to program compatible novak esc's (cyclone & atom). about the other specs, the millenium pro has charge memory, lower voltage threshold (2mv, i think), and different charge profiles. go to the novak website for more info. if youre in the market for a new charger, get the millenium pro because it costs only a bit more than the old millenium plus you can use the built in pit wizard if you have one of their compatible esc's.