I first saw this clock demoed at a recent Tindie / Hackaday Beer and Hacks meetup in Nottingham, and it caught my attention straight away.
The LEDs used on the demo were a bit bright for my liking, so I ordered a kit using Red, Orange and Yellow LEDs (Blue is a bit bright for my liking).
The instructions supplied are very good, and accurately show how to build and use the clock.
I had no problems building it and getting it running, and only took me around 1.5 hours from start to finish. I am quite expedience at building circuits, so would expect it to take a bit longer for less experienced solderers / beginners.
The kit only uses through-hole components, so is very suitable for beginners, and even included a couple of spare parts (just in case they get lost while assembling?)
My main concern about the GPS based clock was if it would be able to receive GPS signals indoors. The instructions and notes do help explain this, and say that a full GPS lock is not required to obtain the time. So even if just 1 satellite is receivable, the time is available.
It did take around 15 minutes to establish the correct time the first time I powered it on, this may just be due to satellite locations, etc.
Overall, I'm very pleased with it, and wouldn't hesitate to recommend others to buy this. It's a great talking point, and tells the time to boot.
Very nicely present kit, good instructions and easy to assemble. Great support from the creator who helped me deal with an issue that was down to the chips I was using having been locked by another EPROM programmer, now resolved with a code update. Full review on my blog: http://blog.tynemouthsoftware.co.uk/2017/12/arduino-eeprom-programmer.html