Well send me a link. I have never seen a 2/3A pack above 1600 mAh. Even MaxAmps has nothing bigger.
My guess is that it's not a 2/3A pack, but rather an AA pack. Those can get up to 2400 and maybe 2600 now.
Like this guy:
http://www.onlybatterypacks.com/showitem.asp?ItemID=10554.16
I made my own out of engergizer 2450Mah NiMH AA cells. Run one in my savage (which has one digital steering servo and one 985MG t/b) and one in my jato, which also runs a digital servo for steering. I have never been able to run either dead in a day. I've burned more than 1/2 gallon in the savage in a single bash session and the pack never showed signs of slowing down. I need more of those days...