Wired published Xiaomi Mi5 review. TL;DR:
Pros: Surprisingly good for an inexpensive phone. Big, bright screen in a slim body. Customizable buttons and an accurate fingerprint sensor. High-resolution camera with four-axis optical image stabilization and 4K video capability. Insanely fast processor with lots of RAM.
Cons: Camera keeps annoyingly refocusing while shooting videos. The black finish is a grime magnet—fingerprints show up instantly. Difficult to find: the Mi 5 is not officially distributed in America or Europe yet, so you have to order it sight-unseen from eBay or a third-party website.