CC, can you go to your local REI store (if you have one) and try it on first? Or, any sporting good store with similar backpacks that you can also tryout.
REI makes great products! I grew up in Seattle and that is the premier outdoors store. Added to that, Eagle Creek is a top quality brand too.
For sure it'll last long, and for sure you're going to get your moneys worth.
The question is, is it the perfect pack for you and will you be unequivocally happy with it? Only you will know that answer after you have strapped it on
Look at Moc, she has like, 8(?) backpacks, And I think that they're all good!