Looks like there's 30% off all Crumpler products at Myer. I first bought a Mantra (or its predecessor if it had a different name) four years ago. After more than four years it's really only discoloured slightly. There's a compact version and a larger 'Travel' version too.
The Mantra: To combine style and comfort with functionality and reliability. The end result: a 15" padded laptop sleeve, fully adjustable padded shoulder straps, hidden zips, internal mesh zippered pouches and an expandable main compartment. A backpack perfect for work, travel and everyday life
Checking what the warranty term is but From a ticket response, Crumpler has a 5 year warranty. I've heard good things about their repair process if you need to use it. The guarantee blurb is here.
That's an insane price for a back pack. I own a crumpler bag, but wouldn't buy one at this price