Edit: I'm stupid and this is an awful deal. Don't get it!
If you don't mind that someone else's grubby fingers touched it, I think this is a pretty good deal. It's slightly cheaper than the AWD-IT deal posted here recently (unfortunately no longer available) and it comes with 8 GB of DDR4. It's used but it comes with a one-year warranty which is the same as if it was new, I think. The RAM is only 2666 MHz. I don't know how much worse that is than the 3000 MHz the motherboard is capable of.
Incidentally, the motherboard has some sick LED lighting which you can see here! https://www.asus.com/uk/Motherboards/Z170-PRO-GAMING/
Please correct me if I said anything wrong or stupid.