One thing I forgot to mention is that I also found the Mercer leather very "water-friendly." I carried my Mercer EW Tote in wind, rain, snow and sleet and it never left a mark on it (and I never water-proofed it either!)
It was always the bag I reached for on my days off and I had the baby with me - I loaded all her stuff inside and carried it without ever giving a second thought to being extra careful with it. My first one (which was used more heavily than my second), didn't have a mark on it when I let it go. My second one didn't either (altho I had that one for a shorter amount of time and didn't use it as much as my first one). In fact, the second one pretty much still looked new when I let it go.