Be careful of GL.iNet's products - some of them say they run OpenWRT, but they don't run stock OpenWRT and instead offer a version of OpenWRT supplied by the CPU manufacturer, with binary drivers and no source code.
Yup, it's specifically a problem if you simply go to Amazon, and shop GL.iNet based on price.
Their GL.iNet SFT-1200 "Opal" router does NOT have ANY OSS firmware options. It's a great travel router for $35 USD, but, alas, they're basically abusing the OpenWrt trademark by advertising it as an OpenWrt router when it is not.
Luckily, I think most of the other ones do have OpenWrt builds, but, if you're going to install OpenWrt manually, might as well get a different/cheaper router from some other manufacturer, like Cudy or Dynalink, which are also supported by OpenWrt, and are very affordable for the hardware that you get.
Yeah, it's probably best to pick something with upstream OpenWRT support and flash it when you get the device. I think that's what grandparent was saying, given that they link to the ToH.
