Router like this are very low spec for example Fritz!Box 3270 has 360 MHz 1 core CPU, 64 Mb of RAM and 16 Mb of Flash. Only thing you can do with them is flashing OpenWrt, but its latest version doesn’t support devices with or less than 8 Mb of flash and 64 Mb of RAM.

I have SV06 and I’m happy with it. It has decent build quality and prints pretty well. It isn’t the best printer, but it will be hard to find something better for that price, especially if you buy refurbished unit from their website. I flashed mine with klipper and you should know that it doesn’t like some sdcars. It also doesn’t have runout sensor. You can ask me if you have some questions.