I have a smaller VB backpack and I love it. I was thinking about updating it (after several vacations, the wear and tear is starting to show). DH wanted a more "manly" backpack since he got stuck with it a lot on this trip, so we bought an Eddie Bauer backpack with a breathable back, but I'll still be bringing the VB backpack along for the lighter days in the park. We also got a larger camera and last year was a little awkward, always juggling it to get to whatever was in the bottom of the pack. If you have a small camera, it really is a great little bag!
Last year I also had the VB wristlet to keep track of my phone and tickets and fast passes. It was the perfect size, but the strap did get on my nerves and it was so bulky that even though it fit in my cargo pocket, I felt weighted down by it. This year I'm going to try the "mini hipster" as a makeshift wallet (with a strap) that can stay in the backpack until DH and I go our separate ways with the kids and then I'll have the essentials with me.
Good luck in what you choose! I wouldn't hesitate to buy another one if I find a pattern I like (I'm hoping the fall 2012 patterns that come out in August will be more appealing for me - mine is in Java Blue, but I haven't liked a pattern since Buttercup).