I've seen very mixed reviews of the Android USB sticks, especially at the low end (~$40 as you say, many are more like $70)... they seem unreliable. They also d

I've seen very mixed reviews of the Android USB sticks, especially at the low end (~$40 as you say, many are more like $70)... they seem unreliable. They also don't have quite the large community hacking on them that the RPi has. Not an expert opinion, just the reason I went with the Pi personally. Also, they run Linux by default, so you don't have to worry about installing it and whether it's going to work.