Pros
It is a zero-hour contract so you can sign up to shifts whenever you're available. The hours can be from 5 hours per shift up to 12, depending on the nature of the job and how much you want to do. Working behind bars, inside arenas, at concerts and at festivals is one of the most fun jobs I've had, and the team is lovely to work with. The job is both easy and hard depending on how busy each event is, but you will always have a break or time to relax between serving customers.
Cons
Sometimes the management and organisation of events can be a bit iffy. Sometimes they don't provide enough information on what you need to do or where to go (esp a problem if you're new) so you feel a bit lost or the event will feel a little disorganised. But only to a mild extent.