Hey Holyschmoley, You really need to think twice before going up to a 2100. I have one that I tried out in my CP. She rally had a hard time getting off of the ground. No problem for the 450 SE or Walker60 size of heli though.
I would recommend not going any higher than a 1500 battery just because of the payload your heli is carrying.

But that is only my opinion!

Michael