I love my FMA Powerlab 8! I charge my 5s 4200mah Hyperion at 5c (21.0 amps) all the time now. All of the equipment is cool to the touch. I'm going to keep buying Hyperion Lipos, they are the most solid performing Lipos for the cost (that I've owned).
If it is 1c charge I will charge just below that rating. For A123's I charge at 10-15 amps. For polyquest 5c 4300mah I charge at 10 amps. Like Brian said, the balance will control the charge rate so they don't stay on those high amps for too long. The polyquest have been slightly puffed but that is from in car use, I haven't noticed any adverse affects from charging e.g. no heat or puffing etc...