This is an amazingly designed little piece of technology. I will definitely be purchasing more. Elegantly constructed, and great functionality. Gordon is brilliant, and has done a great job implementing ecmaScript on hardware this way; truly inspiring.
The only snag has been the unfortunate conflict when broadcasting advertisements that it blocks the process for being able to connect and edit the code for the unit -- but this is a natural outcome of the circumstances involved. I do believe it can be improved, but users should be aware of the potential stumbling block.
I thought I should leave a review here because the shim worked for what I bought it for, even though that wasn't it's intended purpose. Just cut the long parts off using a small pair of side-cutters. Then place the shim between the plastic of the header pins and the Pico itself, then solder the headers as normally installed on the Pico. This allows you to add 8 more 100 mil (0.10") header pins face up for use with a breadboard and male to female prototyping wires. And now you can make use of those tiny pins that looked unusable previously.
Got a little damaged during shipping (it seems someone at royal mail decided to leave my package at the bottom of the stack and load a ton of bricks on top it so the pins were bent. No problem bending them back straight tho). (Raelly there must have been a ton of bricks on top as the packaging was pretty good).
Getting the lights blinking took about 2 minutes (if you are on linux remember to give yourself access to the serial port ;)
Now I just need the next killer IOT idea (and maybe the wifi module and the shim for it.. and the battery.. and lots of other cool toys ;)