I'm using this to flash the esp-wroom-32 module on my pcb, and it's working great. I was previously using the adafruit CP-2104 module, but the automatic bootmode wasn't working for me. This board solved that problem. I did run into two small issues with the ESProg, but those were quickly fixed. My board was expecting 5v, not the default 3.3v. There's a jumper on the bottom to be able to change the switch to support 5v. I also had to swap the TX and RX from what I had previously with the adafruit converter. It's a great little tool.
Works flawlessly, has a great assembly and high-quality components. I particularly like the power switch as you can do the programming without an external power source.
I plan to use it together with a clip with pogo pins for programming my boards without the need for soldering. And it'll also save some space on the boards itself as it eliminates the need for a flash button.