At least for a simple camera I've done that with something that resembled a spherical coordinate system (although maybe not following the usual conventions) and it didn't experience gimbal lock. Effectively the axes rotate with you. It's also very intuitive to work with the code, although probably not very efficient compared to other approaches (but hey it's a camera it's not like there's 10k of them). Once you have the camera orientation you can derive a corresponding rotation matrix to apply to the scene geometry.

I guess what I'm trying to ask is if there's any reason other than efficiency not to do something like that when modeling craft and the like?