This is the new 2017 model with HDR added (something the KU6300 didn't have). It's priced at $550, but Amazon and Best buy have it for 449 right now with free shipping. This is the lowest I've seen it. Like I said, it hasn't been around long.
Was thinking of pulling the trigger on this and worried that posting might cause SD effect while I deliberate, but I gotta give back to the community. This would be my first good post if people like it I might even break 100 rep points
As many know, the Samsung lineup has been used by quite a few as a monitor because of 4:4:4 output, etc.
Also, in case you didn't know about model years for samsung tvs JU (2015), KU (2016), MU (2017).