I think a sound recording of the music in class is fine and is second only to playing in person. With a recording you can try stretching your abilities and don't get to feel nearly as bad if you don't get it right.
On the other hand, as an internet user, I am 100% opposed to video because of the ease with which it can get out of your control into the world of youtube and beyond. I feel almost the same about vocals. They also can get out of your control and have little value to people trying to improve their playing.
So, for me, I am 100% in favor of recording instrumental music in class for class use. I am 100% opposed to video and am not too keen on vocal music.