I don't like how negatively most people seem to think. This looks to be equivalent to putting the M1A into a different stock. It's clearly the same firearm before and after the "lower" is put on it, so it should be fine.
On the AR the loaer is the firearm, which is resrricted. This would make a m14 restricted. If they classified it as a ar variant which likely would happen judging by the bad news, and s&w m&p22.