(not my photo, just a generic image of the bag and a camera which definitely isn't mine!)
When I started this gig, I chose the smallest version of the Lowepro Slingshot to carry my gear around in. Good choice at the time, and I still use it now and then, when I don't need the kitchen sink. For that, I'd take out my second bag - the biggest version of the Slingshot, the 302. My my...thats a heavy bag. Some people have complained about the weight of the empty Retrospective 20 but it is NOTHING compared to my empty Slingshot 302.
As you can see, it's a backpack-style (but only has one strap, it slings diagonally across the back) has a fair few straps and clips and junk, and looks every inch like a camera bag. It screams; "STEAL ME!"
That was my main prerequisite when choosing my next bag - it had to not look quite so much like a bag that might house a few thousand worth of gear. I pretty much decided that when walking through a dark back street in Fortitude Valley at about 11pm after the Simple Plan gig.