Well I'm on the other side Joe, I'm used to travel "heavy" for two reasons. First I can do that cause I myself weigh 100Kgs (~200pds) -tall not fat :? - and Second, I prefer the "better safe" from the "than sorry" part... Afterall, you mention "day trips" in your first post, but I guess a walk around bag trully never leaves your shoulder... well... :roll:
Depending on what lens you have on your camera. Before I got my 17-55, I had the kit lens on my D2H, and could fit a 80-200 on one of the inside pocket and a 85 f/1.8 and a 24-120 VR on the other. But had trouble pulling out my camera quickly, compared to other top load bags.
This bag doesn't offer too much protection, but if it's not leaving your shoulder and you don't swing it around too much, I don't see any problems as a walk around bag.
It's only padded on the bottom of the F-3X. I tried to fit the D2H with 17-55 on it, and a 80-200 in one of its inside pockets, there really isn't much room left for anything else in the main compartment.
Prime lenses fit nicely inside those Domke inserts, I find it a bit hard to get them out.
It's always so hard to find a *perfect* bag, the ones I have are either too small to carry what I want, or too big that I can't fill them with my limited gears.