How does that hardware compare in terms of network throughput and power consumption to MCUs like the Allwinner H2/3? OpenWRT has been ported to that processor and boards like a NanoPI NEO plus a small USB WiFi or a second Ethernet dongle would still cost less, whilst having enough RAM and horsepower to host a full Linux install.
The recommended hardware uses an MT7620N SoC, which while fine will not necessary play as well with wifi compared to an AR9331-based device, like the Gl.iNet series. It'll work but you might find some performance and/or stability issues.
Gl.iNet devices are also available on Amazon if you don't want to wait that long for a bit more, and should (but no guarantee) work fine too.
I'd be very afraid to miss the deadline for Christmas if I ordered something now, though. Perhaps you're closer to them, here in the Nordics delivery easily takes 4 weeks.
http://www.friendlyarm.com/index.php?route=product/product&p...
https://wiki.openwrt.org/doc/hardware/soc/soc.allwinner.sunx...