So I'm finally going to buy my first real Tom Bihn bag (I just got a field journal, which is amazing). I think I'm going to get an ID with a Freudian Slip, but I wanted some opinions on whether this is the best choice for me. I also looked at the Zephyr and the Ego.
I am a Montessori teacher, so I generally have papers to carry back and forth (but not massive amounts of paper), plus my FJN, sometimes my computer (currently a MacBook Pro but soon to be an 11" MacBook Air), a water bottle, my lunch (could be carried separately), and occasionally a change of shoes, as well as miscellaneous items like my wallet, cell phone, and bus tickets. I normally walk (half an hour) and have some problems with my shoulders, so I don't want a bigger bag than I need because that will just encourage me to add more weight.