Need a New BackPack

Okay, so here's the deal. I own five backpacks, all for various needs and applications. I got three for bug out types, I got a heavy gear bag for storm duty ( Tactical Tailor ) and I bought a Victorinox for Urban Travel.

The Victorinox has turned out to be a piece of crap after a year of use.

What I am looking for is a single shoulder style, urban travel pack that will allow me to carry a few pounds of basic gear ( like my 1911 when needed ) and a few daily essentials like powerbars, my Zune/Headphones, a soda or two and my keys.

I don't want any type of aluminum frame, I don't want any multiple day pack that will allow me to pack enough gear for a bug out scenario and I sure as hell don't want any Messenger Bag like the types that have become popular thanks to the infamous Jack Bauer.

So - knowing that. Do any of you have any real suggestions for a reliable, well built, durable, preferably with heavy duty YKK zippers, backpack for the urban environment?

Thanks in advance -

JD