The Casio F-91W has been the model of watch I have been wearing for 7 years! Cheap, Reliable, accurate, and dosent look like shit.
I prefer my screen to be on the warmer-side, so I put the thinnest layer of kapton tape over the screen and it works perfectly!
A Custom PCB for casio watch's that allow custom firmware! I have also implimented neralie time for the sensor watch!
The stock-pcb is now lonely, without any housing to live in :(