I just got an 0610 and it is SWEET. I would definatly try to save up a couple of extra bucks so you can get the 0610. Just make sure you get a PS that can put out atleast 200W, as right now Im stuck with 100 watts which isnt all that bad, but it is definatly limiting how many amps I can charge 5/6s batteries.
haha...I dont know where your getting 420 watts. but your lipo should put out 2,520 watts if those figures were true. because of voltage drop you may get 2000watts out of them, but that doesnt matter anyways. its all about how many amps you put into them when charging.
Say you were to charge them at 5 amps. your going to need a total of 111 watts. battery VoltsX charge rate(in amps) = watts needed.
as stated earlier you need to factor in the chargers 80%(rough figure) efficiency, so 111/.8 = 139 watts.