Vantaggi
Broad range of experiences in different fields available. Able to work in many offices (although don't expect any thanks or incentive for traveling overseas or interstate, being away from your family for long periods of time is expected of you).
Svantaggi
They will hire you on a full-time contract, and charge you out at many times what you actually get paid per hour. When the economy tightens they will almost immediately force you onto leave without pay, no retainers, no accruals of Annual Leave, Sick Leave, Long Service Leave, etc. This time round it has gone for 2 months (new starters with mortgages would be struggling). You sit and wait for a call, and they don't call. So you spend your time off worrying and racking up a phone bill chasing any available work you can get.