Review on OSOYOO ESP8266 Wireless Transceiver Development by Bennie Wilks

ESP-12S is very well known in the Arduino world. It's basically an ESP8266 configured to work with WiFi. Those pins sticking out of the board are for the serial bus, and you communicate with it using "AT" commands. There's nothing new or surprising about it. I think these special ones are a bit pricey. Many people have switched to the slightly more functional ESP-32S. If you can get an ESP-32 for the same price, that's the way to go. In terms of quality and everything else, it lives up to expectations. Hobby class, not aerospace class.