D1 Mini NodeMCU ESP32 ESP-WROOM-32 WLAN WiFi Bluetooth IoT Development Board 5V Compatible for Arduino (5pcs)

No issues. I know that some reviewers stated that they had a board arrive dead but I didn't experience this. 5 out of 5 boards worked perfectly.

I have 35 of these programmed with the ESPixelstick V4 software that's running my Christmas lights. I have a single wireless access point pointing out of a window, and every one of these is picking up a good signal with the built-in wifi antenna. I had some flickering and sync issues last year with some esp8266 D1 minis, but moving to the much faster ESP32's, I had no issues at all this year. And they're cheap too!!

Like these little controllers, I have already used 4 of them around the house. 3 running ESPhome and 1 for a custom spa controller. Small size and pins marked well, no issues. Easy to program over USB.

Let me start by saying, to flash micropython onto this device, you want to grab the Expressif generic esp32/ESP32_GENERIC firmware and use`esptool.py --chip esp32 --port ⋯ --baud 460800 write_flash -z 0x1000 ESP32_GENERIC-⋯.bin`(where ⋯ is the correct port and lastest version.)The baud and offset are VERY IMPORTANT.(I have not been able to determine what version of CircuitPython is compatible.)

The good:And, it's cheap and small.It's an ESP32, not an 8266.It has a Silicon Labs 2104 USB to serial instead of the dreadful CH340.The bad:As other reviews have stated, it's a 150mA regulator. Espressif states 500mA in their ESP32 data sheets.It's width is such that it can't be plugged into a breadboard and still have room to connect wires.Overall:With an upgraded higher output regulator, it would be decent. As it comes configured, I wouldn't feel confident trying to attach LEDs, backlit displays, or anything that requires much power.

This is a great form factor for ESP32 projects that need to be small and compact, versus the more typical "NodeMCU" form factor. I've used several of these for various projects, many are for ESPHome Bluetooth Gateways (extends Bluetooth/ BLE coverage throughout the house) because I can hide them away easily, but also used them for a fingerprint reader project using a R503 fingerprint reader. In my use case, I've powered them through the USB and no issues (can't speak to using the 5V pin). I see they have USB-C versions now, may have to try those out next.

I used these for 5V LED lights using WLED and it worked great. Will buy more of these in the future.

These boards have been perfect for my little projects. I usually only need a few IO pins. The small form factor of these boards make them easy to hide or put in a 3d printed case.