I'm not sure how well the item you linked to would work, but I would like to suggest converting a computer power supply to use to power your battery chargers. I converted a $14 500 watt one and I use it for my A123 charger and sometimes my Duratrax Digital Piranha charger too. It's great, works wonderfully, and was very cheap. There's a lot of good how-to's out there. I just came across
this one. I would suggest looking around for a cheap, high wattage, off-brand power supply to use, since chargers aren't as picky about their power as computers are.
Good luck,
Brijar!!!