I think that the Bantam only adds one more port for a total of two batts at a time, and I don't think that's such a great "multiple battery" improvement.
There are two relatively new chargers that many people report that they like quite a bit and will charge 4 batteries independently.
They are:
1.
http://www.hobbycity.com/hobbyking/s...dProduct=10327
and:
2.
http://www.unitedhobbies.com/hobbyci...dProduct=11170
I have the first one, the "Quattro", and although I'm getting some unexpected results using it to charge Nicad and Nimh batteries, everyone else seems to like how it charges and balances all the other newer technology batteries. As far as my unexpected results with Nicad and Nimh batteries, all I mean is that it appears to report different discharge capacities on batteries from when those same batteries are discharged on other chargers. I still think it's a good charger, and what I'm finding is that I may be the one causing those unexpected results because so many parameters can be set by the user than I may not be using the same parameters exactly that other chargers use (that are hardwired into those chargers and cannot be changed by the user.)
I have no experience with the second one so you can do your own research.
Note that neither is a terribly "powerful" charger (five and six amps per port respectively), certainly nothing in the class of the iChargers (at 20 amps and up to 30 amps for a new one), but either should make a great overnight charger. Being as they both use 12v input, you can use them at the field off of a lead-acid 12v battery as well, and since you can keep 4 batteries charging at the same time, either of those chargers would still probably work well for charging between flights as well.