I'm a sucker for modular crap. I recently bought a modular notebook "system" for $30 (spoiler alert: I hate using the damn thing, but I feel like I have to since I paid so much). I was at a convention Sunday, and they were selling some cool looking modular backpacks. They seemed like really good quality, and I spoke with some people who'd had theirs for years (they were there buying new accessories for theirs).
But in the end the price was just too high. $90 for the main compartment, $65 for the shoulder straps/harness, $15 and $20 for the two pouch attachments I wanted, plus however much they managed to upsell. Just... no. I've been using my $15 WalMart special since 2010--granted, it's falling apart, but I could get another perfectly good backpack for under $50. Plus I recently hassled my husband for getting a $60 backpack--can't be a hypocrite, after all. Still want it though. (I'm so bummed out that modular smartphones failed miserably.)