I've had my timbuk2 messenger for about 9 years now. The inside looks like it got mauled. Lots of tears. But it still holds up rather well. The strap and everything else is very comfortable.

I use it to get groceries once a week. It's come on every vacation I've gone on. I've moved with it. It is not a simple work backpack. It goes with me everywhere. Really great investment.