@FBAwayDays Cardiff were loud but great craic at Wembley in 2012 and gracious in defeat. Wouldn't fancy being on my own in Millwall after the game, but again I don't think you'd be affected unless you went looking for aggro.
@FBAwayDays Luton wasn't scary, it was just deeply unpleasant. A step back into the 80s with the attitudes and songs from their fans. Chelsea is not scary so long as you don't behave like a twat, and keep your celebrations (if you win) inside the ground rather than mouth off on the concourse