As an earlier poster noted, bags are personal. I'll add very personal. That said, I recently purchased a Lowepro Pro Runner 350 AW. You can see it at http://store.lowepro.com/pro-runner-350-aw
(It lists for $219 but you can find it online at most places for $189). This style of bag also comes in smaller and larger sizes.
I bought it because it will hold 2 bodies (6d and T1i) with 2 medium sized lenses attached plus two or three more lenses/flashes. I also really like the accessory compartments and the zippers on the bag--they work really smoothly and you don't have to struggle to get your bag open. And, you can attach a tripod to it (although I don't know how heavy of one). You can also add Lowepro accessories to it such as an extra lens case or water bottle holder. (The bag comes with 2 side water bottle holders, but the water bottle holder I attached to the bag will hold larger bottles and hold them more securely.)
Someone also mentioned the Lowepro bag finder. It may work in some cases, but when I entered what I wanted to put in the bag, it provided choices that would not work and omitted many that would. I found the Pro Runner 350 AW by looking through their site the old-fashioned way.
Before getting the bag I did, I looked at a lot of bag companies. The other bag company that I strongly considered was Think Tank. I bought the Lowepro bag over the Think Tank one because while both would hold the gear I needed, the Lowepro bag had a smaller footprint. The smaller Think Tank bags would hold my gear but not configured as needed. And, we are back to where we started--it's very personal.
And, one final point: Be sure to buy your bag from a place you can return it. You won't really know for sure it works for you in the way you want it to work for you until you put all your stuff in it.
Good luck and let us know what you get.