If you're going to do a multiple pack charger, go with the Hitech. You don't want a lower quality imitation product where if you lose one or two ports, you're stuck with that big thing functioning the same as just buying two chargers.

Although, that being said, you may find just buying another single charger and carrying two is the way to go. I sometimes race three classes in a single day and that's the route I went. Rarely will you see anyone needing or using all four ports on anything that will do more than two packs at a time anyway.