So I see the R7III are now on preorder for $1800 each. I was reading and couldn't really find a difference between the two. Can someone shed some light on this for me? I see the R7II are $1279 until December 5th. I keep saying I was going to buy a set of the R7II but once I heard the R7III were coming out I decided to wait to see if the wait was worth it. So is the R7III worth the extra $521 each? That is another thousand dollars when you buy the pair.