This Porter backpack looks like a well-crafted piece of equipment with a very nice colourway. But I cannot imagine why anyone would pay S$330 for backpack. Seriously, they should just sell Porter logos as sew-ons or iron-ons for your existing equipment at S$199.99 and get on with it.
I see myself as a backpack man and my pick for a good, reliable backpack would be almost anything by Herschel, like this one for less than a third of the Porter price.