I had tried 6 different ones before I ended up on the Apple TV.
MiBox, Fire Stick, few random ones in singapore (testing in store they are super responsive but when you get home they are slow or slow down)
Couldn’t get the shield in Singapore. Saw it here in Taiwan.
The mibox was the best I tried but the issue was when at 4k it’s laggy. Content plays without issue but navigating around is frustrating. And if it’s at 1080 it’s fast but when 4k content displays it goes crazy while it switches.
Which one did you buy? There is a huge variation in quality, e.g. nVidia Sheild/Google TV vs. a Mi Box / FireTV, etc.
I think you have to compare Apple vs Apples. Compare the Apple TV to a equivalently priced Android TV.