That's roughly 0.1C which is the recommended charge rate for these batteries (for long life). Charging faster will get you back in the air at the possible cost of shortened battery life. It's a trade-off.

Even though I charge at 1C in the field, I usually charge at approximately 0.1C rate. The problem I have is that I usually just replace battery packs when I feel that they are not going to be reliable to me. I value my planes more than what a replacement battery pack costs.

CGr.