Moble Broadband with Unmetered Content

Hey guys,

I am looking at getting mobile broadband data sim for when i'm away from home. Looking at both prepaid and post paid.

I probably need about 5gb per month.
Would like to have unmetered Iview/google music access if possible.

Currently looking at optus —> unmetered on postpaid but pricey
Vs OVO or virgin

Any other suggestions

Thanks