OK, I never used lock switch for orientation and for me it makes more sense to be a mute switch but here is my issue. Holding down on the volume down switch also mutes which is something I thought Apple were against - 2 buttons almost next to each other doing the same thing? If I have the volume up high and want to lower it and not mute it, I would prefer to just hold down until I reach the desired volume instead of having to tap down a few times.
My final issue is with Mute only being a system mute. I wish it muted all sounds from the iPad and not just the delivered system sounds.