I have a few projects on the go using ESP12 and ESP07. I have used maybe 50 or so and am seeing a failure rate of around 20%. As a failure rate this doesn't really concern me though it is very high. The faulty ones have no wifi though they think they have, no errors or other things amiss in the serial data or IO control.
The problem is that by the time I know they don't work they are already soldered to their PCB and are pigs to replace. So the question is did I get bad batches or am I building a bed of nails to try them before I solder them to the PCB.
Any one else got any failure to work figures for them or advice on where to buy from? I normally just get the cheapest off Aliexpress.