I recently upgraded a forum to Xenforo 2.
This was a major upgrade with a bit of a learning curve to convert everything from the previous version, Xenforo 1.5.21.
I won’t pretend it wasn’t challenging but it was made a lot easier by the help and support from four individuals in particular who went out of their way to help during this process and to provide fast support, even on the weekend and late at night to get the forums back online.
Second, Russ from Pixel Exit. Pixel Exit are the designers of some excellent Xenforo forum themes or styles. Russ never seems to sleep! It seems like no matter what day of the week or what hour of the day or night I submitted a question in a support ticket, he was back with a solution usually within an hour or two and sometimes within a matter of minutes.