Charging is a bit of a pain, but pretty much any RC Lipo balance charger will work fine. It depends how fast you want to recharge the packs and what size packs you choose to use, as some chargers only have a 5S or 6S upper limit (although some of the top end ones will now charge 10S.
HK wouldn't be able to advise you well, as they won't know your battery pack configuration - this is an oddball use of these packs, not something they or the chargers are designed for.
For example, I use 4off 5S packs in my folding bike. The pack is configured so that it is really a 10S 2P pack, with two pairs of parallel connected (at the cell level) packs wired in series to give me the right configuration. I charge this pack with two 5S capable chargers, but have to split the pack back to two 5S 2P packs because I run both chargers from a common 12V supply.
The chargers you choose to use will depend very much on the topology you opt for when building the battery pack up. There are very few 10S capable chargers about, HK only stock two, this one: http://www.hobbyking.com/hobbyking/stor ... oduct=6609
and this one: http://www.hobbyking.com/hobbyking/stor ... duct=11597
I've not used either, so can't say how good they are. The difference between the two seems to be that the 1010 is 300W and the 3010 is 1000W, so will charge faster. Both will need suitable power supplies (they aren't mains powered, as the RC boys charge in the field from car batteries). You will either need to take the battery apart to charge it in sections, or get enough chargers and power supplies to allow charging with the pack assembled. You'll need to maintain isolation if you go for the multiple charger approach, which means careful choice of isolated power supplies to run the chargers. Either way you need to bring all the battery connectors out so they can be hooked up to the charger - these chargers all balance charge by sensing cell voltage from the multi-pin balance connectors on the battery packs.