I've got a first gen (I think) Hyperion 720i and am pretty happy with it.
Can do up to 20A and big packs if you want. Can also link 2 of them together for charging and balancing multiple packs.
You need to pay attention to the balancing plugs on your packs and get the correct balancing board adapter if you go this route. The temp sensor add-on is nice insurance too. I stick this in my charging sack and if the temp goes over 50 degrees Celsius charging stops.
Check out Big Squid RC's reviews of a few chargers