if you have downloaded files from navifirm - TWO qs

1. did you use nokia care or prod external?
2. what did you use to flash with?

I have a N9 that is still at PR1.0 that i will have to update twice it seems as i dont think you can just go from 1.0 to 1.2 - correct?
So...id like the most reliable - least painful way

EDIT: im going to post this in the official PR1.2 page - dont want to get the wrath of someone we know