Test of 5 AC-DC PSUs cheaper than $1.5

I need  220AC to 5V PSU for exhaust fan controller, the trickiest part – it should be as small as possible. The main load is LEDs, same time supplied voltage should be clean enough for analog to digital conversions doing by attiny85. So I bought and test 6 different PSU. Because of seller mistake one of them turned up to be 220 to 12V PSU, so only 5 of them were tested.

All of them produces awful output exception of #1 and #3 (hilink)
The winner is #1, it’s one of the smallest (12X25X18 mm), one of the cheapest ($0.77), rated at 5V 700mA power supply.
No one of them (with exception of hi-link) doesn’t look safe enought to be treated as galvanic isolated PSU.
Here is a table for quick comparison, but out of the box (without changing capacitors or adding filters), only #1 and #3 worth to buy:

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Simple temperature controlled fan regulator

Some time ago I pulled out temperature fan controller from one of old ATX PSU.
With 12.2V input it provides 4.5V at 25°C and raises output voltage till 11.8V at ~70°C. After changing Q2 to higher voltage transistor and tuning of R4-R5 this divider this controller should be suitable for 12V fans with 24/36/48V input.
Here is result of my reverse engineered schematic: