Proper Linux is only worth the difference if you can actually fit the OS and your application in the available RAM (good luck) and the part has mainstream kernel support and available documentation. Otherwise you are buying into a literally throwaway platform that will become a useless piece of e-junk the moment the vendor stops updating their copy of Linux with patched in various binary blobs necessary to make the thing work.
The VoCore website only links to binaries, no source code (only some patch files) for their kernels and OpenWRT builds (GPL?), the wifi driver Github has "This feed enable using MTK/Ralink official wifi driver for the latest linux kernel 4.14/openwrt." in the description - current mainline is at 6.5.3 ...
Their OpenWRT binaries are also ancient - the latest they offer for download is 19.07.03 which is 3 years old. Not great, given what this is meant to be used for. I guess security is not high on their priority list.
Also the amount of chinglish on the website ("note: normally, we upgrade or fix brick are using Firmware. Flash Image is a clone of the full flash, for professional usage only. ") doesn't exactly bode well for good quality English documentation availability.
Ship an ancient, outdated Linux or Android image, no or incomplete sources, poor or no English documentation - and good luck to anyone trying to make such board work.
The hardware could be the best in the world - but this poor ecosystem support is the bane of most Chinese SBC and the reason why almost everyone uses Raspberry Pi, despite it certainly not being neither the cheapest, most powerful or having lowest power consumption.