I posted the following in another thread about "non-camera" camera bags...
Adam, both the 2 and 4-Bangers are symmetrical. The removable straps can be oriented either way. As shipped and as shown on the 5.11 site -the bag would be over the left shoulder and sitting at the right hip. I flipped mine as I prefer to reach across my body into a bag.
I bought three of these inserts:
http://www.amazon.com/gp/product/B008UVIT7M/ref=oh_details_o01_s00_i00?ie=UTF8&psc=1
One pops right into the 2-Banger. The lid is a bit tight and I do not typically use it on a walk. I had a seamstress shorten one of the two remaining inserts to fit along with the last unmodified insert in the 4-Banger which is about 50% longer, but otherwise dimensionally identical to the smaller 2-Banger.
The 2-Banger (which I prefer) is a bit smaller, especially in height, but similar to a Billingham Leica bag. It fits a lensed M body, an extra lens, and a few rolls in the main, zippered compartment. Wallet, keys, etc. in the front zippered compartment. The Velcro "looped fastener" pocket is a bit wonky and I am considering having the loops removed and replaced with a simple strip of Velcro.
At any rate, a handsome, fairly well made (considering price), light bag that is well suited for hikes, etc.