Truly great little boards. Very well packed, thank you merchant - great as always.
Good quality, I didn't expect to get them in tape :) . ESP-01S have 8Mbit flash memory as described. But in those modules I got, the flash need to change SPI mode to DOUT otherwise esp8266 will hang at boot with 'csum err' (I'm attaching esp-tool window screenshot too with working setup).