5 sourced reports, with what to check before you buy. Each one links to the page it was reported on.
A Yandex Market owner reports the screen went dark and showed green lines after ~2 months, though it did not recur.
What to check. A display defect (green lines / screen going dark) is the highest-cost failure here; buyers should keep the unit within warranty in case it recurs, since a panel replacement is expensive.
Reported on: market.yandex.ru
A Turkish owner reports the battery and fast-charge life dropped noticeably within about 6 months of ownership.
What to check. A TR buyer should treat battery longevity as a known weak point and check whether the unit is still under warranty before the ~6-month mark if drain becomes severe.
Reported on: sikayetvar.com
Polish owners report the battery drains very quickly in some situations, while charging itself works fine.
What to check. EU buyers should expect variable battery life; if drain is severe, verify warranty coverage early since the battery is a common complaint.
Reported on: mgsm.pl
Same Polish EU-market source as above: the phone's body heats up noticeably near the cameras when running demanding software.
What to check. EU buyers who game or run heavy apps should expect noticeable heat near the camera module; this is a comfort concern more than a failure.
Reported on: mgsm.pl
Xiaomi's official FAQ states that a slight red/green tint when viewing the OLED at an angle is normal, not a defect.
What to check. Not every color shift is a defect; a mild tint at an angle is expected OLED behavior, while persistent green lines or a full green screen (as in other reports) are not.
Reported on: mi.com
Kriko reads a listing and tells you which of these apply to that exact product. It runs on your computer, needs no account and is free.
These reports come from the pages linked under each item: owner forums, repair guides and workshops. They are not a diagnosis of any one unit, and a careful check of the one you are buying still applies.
Text from the Kriko Smartphones catalog, version 0.1.1, under the CC-BY-SA-4.0 license.
