Steve, without actually using any of them or having any first hand knowledge, in my research I found that a pair of Astroflight 109s was the cheapest way to go. You can go with the more expensive chargers like the Orbit and Schulze, but you only gain easier firmware updating, more volts and/or amps that you won't need with those batteries, and computer interfacing. I'm also fairly certain Tony has already discussed his choices in chargers somewhere on RCu.