Flashed and set up my F5122 based on the instructions and comments in the thread. Thanks to everyone!

My limited experience so far:

• UI is smooth but not dramatically better than Jolla1, swipe from the edge is not always registered
• Double tap to wake does not work
• The photo camera quality is currently much worse than on the Jolla 1 (I really hope this changes with the official version)
• Video recording does not start
• The 64gb SDcard from my Jolla1 cannot be mounted
• GPS - satellites are visible, but I could not get lock from the window ledge
• Battery life with WiFi on and no SIMs seems to be very good

I guess this is what I have noticed, the rest is working well/as expected.