The 2c charging is supposed to cut the life of the cells, but with modern packs (20+c discharge) that might not be a problem anymore. I still 1c charge mine.

Coolhand_country uses these battery packs (3800 i think) and even used them in a 12s config in his truggy/mt HB thing. I'm sure he'll chime in about them

What are you using to balance these (tap wise)?

I have only heard good things about these packs.

The price of these are a bit higher because the chemistry is so much safer then Lipo. When Apogee provides more pack options (4S etc), I'll probably get some.

They now have 2s through 6s in the 3800's

I have always used an Astro Blinky. However, I am now trying a GP Equinox with optional charge leads to allow 5 amp charging and balancing through the unit. It should give me better life out of my packs, but only time will tell.