Earlier on today, we posted a leak OS for BlackBerry 10 devices except for the STL100-1. Users with an STL100-1 device can now join in on the fun.
User BerryOutsider from the CB forums has reported a restore from 1055 and has had no problems. BerryOutsider also recommends to let BBM restore your Groups and Contacts before you perform a full restore.
Read my full “How to” on loading a BlackBerry 10 OS, including possibly all the questions you could have. (Believe me, it’s as extensive as it gets)