Because I built a big library of modules to the PICs and dsPICs over the years, it will be much faster for me to use a previously built and debuged DS1307 RTC module say to integrate into other projects.
Also it was easy and cheap to get pic products in our part of the world. very few people used other types.
One strange incident with PIC is I designed 7 clocks that display date and time for a local pharmatical research company which should be synchronized.
I made one master clock and 6 slaves, the master clock displays date and time and sends this data using RS-485 to the rest of the clocks to display.
I used PIC16F77 chips in each clock at 19200BPS.
the clocks worked perfectly for 2 years then only the master clock worked, which means communication error. I replaced the master clock with a new board and other clocks still wouldn't accept the incomming data. After looking carefully into serial port it turned out if I inserted 1msec delay after each character sent the other displays will work fine and accept the data. Why did the code work for 2 years then stop? I'm sure its not my fault but the PICs have a mind of their own!
Mahmood