I posted earlier about the new backpack strap placement on the Synapse 19. Sadly, I ended up returning my black S19 because it didn't fit me securely. The most frustrating thing about doing this was the loss of the fitted slot for the Guardian Light (a feature of the new style), which I'd been looking forward to having. A light on the backpack would have made it a lot safer for me to walk home from work.
For those of you with the older-style S19, have you found a way to attach lighting to it, so that you can be seen by drivers while walking or biking?
I have tried hanging the light from one of the zippers, but it flops around and is annoying.