A pretty good price for a (still) great compact camera. The mark IV is not the latest one but has all the important tangible features (960FPS slow mo, 4k video, EVF). The newer mark V has improved AF. A comparison of all RX100 models can be found here - unfortunately there is not much real news about a mark VI. At $772 after cashback +$10 for delivery it is about $70 cheaper than grey imports and is a very good deal if you are in the market for the a camera from the best premium compact line.
Alternatively, if you dislike Sony, the Panasonic LX10 (which is almost comparable to the RX100, but minus EVF) can be had for $650 delivered. A comparison of the LX10 and RX100 IV features can be found here. The TL;DR is that the LX10 has the 4K photo mode which is pretty good, and a faster lens open, but the RX100 has the all important EVF, a 960FPS slow motion mode and faster burst shooting (but not as fast as 4K photo bursts)
Thanks to cjmorgan87 for pointing out that camera warehouse had it at the same price and includes a pair of headphones!
$100 cash back available from Sony
Original 20% off Selected Big Brand Products @ eBay Deal Post
Is click and collect free? or $22 delivery as well