Like Steve said my RB5 with a 13.5 DUO geared 76/31 with a IB3800 35C lipo only uses 860mah in a qualifier and about 1000 in an 8 min main.

My b44 with a 7.5 DUO and a SMC 4900 28C lipo used about 1300mah in an 8 min main.

A 3200 will be fine for a 10.5 2wd buggy or truck.