I plan on getting two maxamps 7.4v 5000HV packs. From my understanding this setup will charge and balance two 2s packs at the same time. I will just need a y-harness.

http://www.boomboombatteries.com/product_p/lba10.htm (2x)
http://www.boomboombatteries.com/pro.../eos_5i_ac.htm
http://www.maxamps.com/Lipo-5000-74-Pack.htm (2x)

I also have a Low voltage cut-off question. If I am running these two packs in parallel what should be my low voltage cut-off be set at? My understanding is 3v per cell, so it would have to be set at 12v right?