Bag recommendations please

I bought the Lowepro Slingshot 200 and didn't think the strap across the front side of the chest would bother me, but oh boy, does it bug the hell out of me.

I travel a lot and want to bring all of my equipment with me. Other than the Lowepro, I've been using Canon 2400 bag. But I just got my 70-200mm f4 today and obviously, I'm not going to be able to fit everything.

I'm currently leaning towards a backpack but wouldn't be opposed to a shoulder bag. I also plan on getting a monopod in the future. I'm currently taking a look at the Lowepro flipside at the moment and it looks pretty good. Just debating on 200 vs 300 and again, other suggestions are welcome.

So what I need to fit is:

• 17-85mm which the ability for the bag to fit 24-70mm or a 17-55mm as I will eventually upgrade my 17-85mm to either of these two lenses and then get rid of my 17-85mm.
  
• 430EXII flash
  
• 70-200mm f4
  
• My Canon Battery Charger
  
• Eneloop Battery Charger
  
• Rocket Blower

You say you didn't like the strap across the chest but don't way what you're looking for. Do you want a shoulder bag that is comfortable to carry over one shoulder or do you want a backpack with normal straps so there's nothing across your chest?

Oops, I did leave that out, didn't I? I'm looking for a backpack but I wouldn't be opposed to a shoulder bag to replace the 2400 bag. I'm thinking of a Lowepro Flipside at the moment. Any other suggestions are completely welcome. And if the suggestion is a Flipside, which model do you think would adequately fit my gear.

For shoulder bag that you will be working out of, I'd go with Domke. Either an F2 or F1-X either are bigger bags that you can fit your gear plus some into. I use an F2 and I routinely carry either of two options - 16-35, 35L, 85L and 135L. Or a 16-35, 24-70 and 70-200 2.8 IS.

Along with either of those setups, I normally carry two 580s (sometimes 3), poverty wizards, filters, cleaning kit and large blower, etc..

I love my Think Tank StreetWalker backpack. It is well built, light, comfortable and easily holds all my gear. The StreetWalker Pro is a little bit bigger if you think you will need more room in the future.

My backpack is the ThinkTank Rotation 360, which is expensive, but allows you to access it without taking it off. My favorite pack. I don't think it looks particularly like a camera pack as well.