I have a fire TV box (2015) and various sticks. The fire devices don't have HD audio pass-through, has 10bit input but not output 10bit, and only does 4K UHD at 30 FPS, not 60 FPS.
I only have local content, and if I rip into 4K 10bit HEVC, the box chokes.
I can VPN and use US Amazon videos, but can't watch CDN content, even with CDN prime.
With the above said, if you're okay with the limitations, then this stick, although a bit slow, with suffice.
If you're a more advanced user, then get a shield TV. I researched the Mi box and there appears to be a bad Netflix bug present in the hardware.