Whichever is best for the occasion.
What's your opinion on trilbys? I'm off to a gangster-themed party later in the month, and need a suitably 30s hat.
( The Mock TurtIe ™ --- Thinks you are a cunt, on, Sat 27 Jun 2009, 0:24, archived)

I saw some SKA enjoyers wearing some, earlier.
I didn't think much of it.
( Jam Master Geordie Hero of B3ta., Sat 27 Jun 2009, 0:30, archived)