Internally they are total nightmare, even screws sucks. Electrically it is horror, frequently they just burn out.
UV lamps live around 1/10-1/5 of normal time because they are made by morons. Fans also live 4-8 months and die in pain.
Total lack of filters. UV light leaks.
Nice thing that due to huge price hikes in 2020 - early 2021 they had been mostly replaced by normal domestic devices made by engineers and from more or less proper parts.
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