AD825 isn't rail-to-rail but it is close. However, it is still a mono channel and there is the concern over its 8 ohm output impedance. AD827 doesn't have a lot of voltage swing on low impedance load or current output as well. Also the output impedance is 15 ohm, worst than AD825.
These are the kind of opamp that are more suitable if there is a buffer stage followed.
Edited by ClieOS - 7/8/13 at 5:43am