Before last semester, I invested in a Zuca frame and insert.  I have the brown frame and "calypso" (turquoise/brown) insert.  I'm not, by any means, a wealthy person.  I work part-time and get financial aid to pay for school, so the $145 investment was pretty significant.  I have not, however, regretted even one penny of that investment.

The Zuca frame is beyond sturdy.  It is a powerhouse.  The people at Zuca claim it can support 300 lbs, I think they are being conservative.  I bet it could support well more than that.  The real brilliance is in the holes.  Several strategically placed holes in the frame reduce the weight without compromising the structural integrity.

The bag is well-made and beautifully designed.  There are outer pockets for things you need to get to quickly, like cellphones and keys. The inside of the door has several pockets, including one large pocket that I have found to be especially handy.  Best of all, the inside of the bag itself is completely open, meaning there is a ton of room for your books and other stuff.  My Zuca right now has three large science and math textbooks and several notebooks in it. I could never hope to carry that much in a regular backpack.  Because the design allows your books to sit upright, they are protected from damage that would be typical of carting them around.

I only have a couple of small complaints about the product.  I personally don't find the lighted wheels to be that charming.  I don't really like the attention they get, either.  People are always commenting on them as I pull it down the hall and it gets embarassing.  The Zuca website has instructions on turning the lights off, but it is rather involved and I'm not particularly handy.  I wish that they would allow you to choose lights or no lights when you order.

My other issue is that after a few months of use on the of velcro straps on the inside of the door has started to come off.  I'm not down rating it for this because I've never talked to customer service and it may be an issue covered by the warranty.  It's not a big enough deal that I feel compelled to do something about it immediately, and it doesn't really interfere with the use of the bag.

I'm actually thinking about getting a second insert, just because they are so much fun (though I wish there was a more attractive pink insert available).  The inserts themselves are surprisingly affordable, at around $45 (sometimes a little more or a little less depending on the style).  The bulk of the investment is in the frame, and there is no reason to get more than one of those!

By the way, it really does climb stairs very easily.  I usually just carry it up, but on days when I am feeling lazy I have no problem pulling it up the stairs.  I also haven't had any problems with it tilting or tipping.  People I see with rolling backpacks seem to lose control of them all the time, or they fall over the second they release the handle.  This definitely is not in danger of falling over or careening out of control.

And one more thing, this little bag is a real conversation starter.  People are always asking me about it and wanting to know where they can find one.  I was the only one on campus with one last semester, but I wouldn't be surprised to see a couple more next semester, just because people have been so impressed by the one I have.