like i mentioned, if you don't mind paying roughly $2500/month for 7years to pay off the loan, it's fine.. 'Cause you gonna have employment with Jetstar Asia, so it's quite safe if you don't lose the job
but people will have to factor in being income-less for 18months.
Jetstar Asia never mention anything about allowance other than lodging being provided in AUS and HKG(with food as well)
during the initial 6months in SIN ground school you might still be able to find ways to earn something. But when you head to AUS, things will be different..