Have you tried looking in TK Maxx? I find that they have brand name packs such as Jansport at a fraction of high street prices.

I like the Jansport Super Break rolling backpack. It's small (same size as their regular backpack) but quite lightweight but does not ahve a specialized laptop sleeve. Also look out for their "Driver 8" style which much bigger and deeper and just at the maximum size and has a dedicated laptop area as well.

30Q is a rather tough.

The ones below are above 30Q, but you may want to look at them anyway:

Check out A Saks. This style has a padded section for your laptop

Or how about the Hedgren brand? They have some affordably priced laptop bags that are younger looking and a little dressier looking.

If you're looking for something you can vacation in, you might want to look at multipupose bags such as the Eagle Creek Switchback. Most laptop bags will not be large enough to vacation with.

Also look for some regular rolling backpacks too. I find that if packed properly, you don't really need the special padding.

Good Luck