I have the same issue but when I open the maps app first and then activate GPS it connects within 10 seconds. Don't know why though.
If u came from latest OOS 10.0.1 u r Ok. Latest firmware already aboard.Great work. Everything works very well. What a bliss moving on from OOS10.
I only had trouble receiving phone calls, the solution was to set a standard app for phone calls in settings.
Edit: By the way, I flashed the rom without flashing firmware (from OOS10.0.1). Can it hurt? Everything seems to be working great...