Good bag/backpack?

I have a Tamrac 5502 but don't really love it. I'd like to get a backpack to hold my new T2i, 18-55, 50-250, 50mm and accessories. Is the Canon 200 EG a good bag for the money? I don't really like the Tamrac because it gets annoying if you carry it around all day. I think a backpack type of bag would be much more comfortable.
Thanks

Welcome to POTN.

My favorite backpack is the Think Tank Rotation 360. You can access it without removing it (the only true backpack that does this), and you can use the bottom section as a beltpack if you're not carrying a lot of things around. You have to take a look at the videos to get a sense of this.

You pay a premium for the pack, but it's built like a tank, has the best shoulder strap and belt padding that I know of, and has the above features that can't be beat.