I think the unique washing process and some of the hardware reflect the price of the denim bags. The Manhattan PM has just as much leather and hardware but it's made out of canvas. They're both the same price. I'd like to think that LV considers the pricing when looking at the processes and the detail it took to make each bag. If you really think of it, all LV is overpriced.
It's easy to look at something and think, plastic, can't be worth it. But you don't really know what goes behind making it. So my vote is for the entire LV collection.