I have attempted no fewer than 7 times to join a server between fresh restarts, rebuilding database, opening ports on router. And before you ask, it's a fresh install today.
It's that bad on one occasion I waited, after recording 10 mins of trying to join, encoding the 3.8GB file to webm (9 minutes) for youtube upload (14 mins) and writing this post (7 minutes) still not joined the server. watched squad members leave and join, but I have yet to have my first MP battle.
Don't let my level confuse you either, some how I registered as playing on a Map even though it never loaded.
see for yourself, currently at 47 mins of trying to load into that server, Utter S***.