Looking for a bag recommendation

http://bagfinder.lowepro.com/lp/choose-profile

Lowepro flipside 400 seems to fit the bill.. Its secure, could hold all the stuff you mention, is well made and you can get stuff out without putting it down if you do the waist strap up and then spin the bag around to you front.

I have the 300 because I have less lenses to hold to hold (7D, sigma 50mm 1.4, 17-50mm OS HSM, canon g12, memory card case, rocket blower etc) and it works wonderfully.

It's difficult to buy camera bags online, sight unseen. You can't get a good sense for the size and how well it fits your gear unless you see it in person.

I think Lowepro makes a line called Stealth Photographer. That's where I looked when I needed a bag because I wanted something for over the shoulder with accessibility when I needed it. I also needed something that would carry all my two cameras and lenses. That said, my "Stealth Photographer" bag is rather big and not very stealth. It has room for about 4 decent size lenses and two camera bodies plus accessories. You can probably find something a much more comfortable size in the same lineup.
For example: When I photograph a wedding, I'll put use it to transfer everything to the locations and carry a 60D, 20D, 24-70 2.8, 17-40 f4, 70-200 f4, and 50 1.8. I'll also have a couple filters that digital can't do for me, memory cards in the carrying case that came with the bag, light meter, and a couple other small things like lens brushes or wipes. Heck, it also has room for my laptop.
I need something smaller for when I'm just carrying a camera and an extra lens...haha

First, I agree with Dan that shopping for a camera bag is very difficult online. It has to fit you, almost as if you were buying shoes. Second, I have the Lowepro Flipside 300 and I don't find it easy to get equipment in or out without putting it on the ground. I like shoulder bags for working out of the bag, particularly those made by Domke, and their J3 might be just the right size for your equipment + a flash and a couple of other extras. But, again, try it on. Visit a friendly brick-and-mortar store with everything you are planning to carry in the bag and take enough time to make sure you like how everything fits. If that is impossible, and you have to shop online, make sure that you can return the bag for no charge other than shipping.

For me, at that sort of gig, I'd want to travel as light as possible - one DX body with an 18-200 Nikkor or 2FX bodies, one with a 24-70 nikkor and the other with a 70-200, and forget fiddling in a bag. The D7000 is excellent at high ISO settings.

I agree that is very difficult to shop for bags online, it's almost like shopping for shoes . Usually what winds up happening is that you accumulate a bunch of bags and each one has it's purpose. I have about 6 different bags myself, from large, medium to small. I pick one depending on the circumstances. With that said, I know LowenPro is a very good brand since I own one myself, but you might also want to check out Tenba http://www.tenba.com/ .

They make very good, sturdy well thought-out photographic bags. The zippers are very sturdy which is what I like, because I had too many mishaps with zippers failing on me. They are also weather proof and most come with an additional water proof bag in case of heavy down pours.

Tenba bags are like the Bags made by photographers for photographers. I like the older ones better than the newer models that have too many slots for stuff like iPods, cell phones and other nonsense.

It's difficult to buy camera bags online, sight unseen. You can't get a good sense for the size and how well it fits your gear unless you see it in person.

+1 on what Dan said there. Additionally, even though it may fit all your gear, it may not fit you, or what looked a good feature on the website/catalog ends up being annoying and in the way in person. I bought a Kata sling/backpack bag in person, at Unique Photo in Northern NJ. It works well, though I find it more difficult to use as a sling than I thought I would. But I love the bright yellow-orange lining, so all that black camera stuff doesn't get lost in the shadows of a black-lined or grey-lined bag.

Tamrac also has a huge line of bags in nearly every shape and size you might need. But again, nothing beats seeing them in person...

I went a few weeks looking for the right bag and as mentioned nothing beat going to the store and trying some on. I ended up with the Kata 3N1-22. It has a very flexible approach to storing gear as well as being able to go from sling to backpack. I am able to carry a body or two, 2-4 lenses, a small netbook/iPad, bunch of cables and accessories like flash, cards, filters, etc. I found mine at B&H. It also has and optional piece that will let you strap on a tripod to it. So far the bag is very sturdy, good weatherproofing, came with a wet weather cover and is fairly light weight.
http://www.kata-bags.com/