Pros:
Simple, compact design
Good organization pockets
Weatherproof lining
Quick access pocket
Sewn in shoulder strap for good stability
Small size is great for 13" MacBook Pro

Cons:
Velcro closure
No grab strap
No laptop sleeve

I was looking for a bag to haul my MacBook Pro 13" and work papers to and from my work. I wanted something compact, light, and comfortable and in a fairly conservative color. The small Timbuk2 Classic fit the bill. I really like this bag, although there are a few additional features I wish it had. I tried out this bag as well as the Timbuk2 D-lux, Timbuk2 Commuter, and Patagonia Half Mass in a local store before deciding on the small Timbuk2 classic.

===========PROS===========
1. Design.  Simple bag. Weather proof lining.  Organization pockets on inside for your iPod, phone, keys, pens, etc. Has a quick release extension to ease getting it on, but I don't find that I every need to use it with the small bag. adding it

2. Size.  The small Timbuk2 is the perfect width for a MacBook Pro 13" and 8.5x11 inch papers without a lot of extra room on the sides for things to jostle around or get lost in the bottom. There isn't much extra room after putting in a laptop and few textbooks, but I found that the weight of the full small bag is about as much as I would want to carry in a messenger bag that puts most of the weight on one shoulder. The medium sized bag seemed to be a big step up in size and was too bulky for me. For days when I need more room, like for workout clothes, I just bring a second bag rather than carry around extra room with me every day. (If you have large bulky, but relatively light, items to carry around then you may want the medium or large bag.)

3. Neapolitan Pocket. So handy to have a pocket you can access without opening the bag. Enough said.

4. Divider.  A pleasant surprise here. I was disappointed that the divider was not suitable for my laptop (see below) and had considered cutting the darn thing out of the bag. However, now I find myself using it all the time! It is a great for storing papers/reports so they are both protected and easily accessible. Sit down on the subway...pull out a report. Super!

5. The Shoulder Strap.  The strap sewn in along both sides of the bag and is not removable. Having the sturdy wide strap sewn gives the bag a lot of stability. Bags with straps that clip on, swivel and pivot at the point of attachment. This bag doesn't wobble like that.

===========CONS===========
1. Velcro.  The Timbuk2 bag has both clips and velcro for securing the flap. I hate the velcro. It is unnecessary because it already has clips, but worse it is noisy. I am reluctant to open the bag during a meeting because of the loud rIIIIpping sound it will create. There is no discrete way to open this bag. (Note: The velcro closure could be negated covering it with a velcro hook strip which I will do at some point.)

2. No grab strap. Other than the shoulder strap, there is no handle on the bag. I often find myself grabbing for a handle on the top of the bag which doesn't exist. You can get a grab handle if you build a custom Timbuk2 bag on their website, but you pay twice as much for the bag.

3.  No laptop sleeve.  Although the bag has a built-in divider which fits the MacBook Pro perfectly, only the inside side is padded (see my video). There is no padding on the outside or bottom of the divider. This means that if you set down your bag hard on the floor, you run the risk of damaging your laptop. I just use my existing neoprene sleeve with my laptop. It is too bulky to fit into the divider, but is quite secure in the main compartment of the bag. (Note: the D-Lux version does have a padded laptop sleeve. See my discussion  on other bags below for why it didn't work for me)

===========Other bags I considered===========
Timbuk2 D-Lux: It has a padded laptop sleeve (although I wasn't impressed by the padding at the bottom of the sleeve), but it doesn't come in black which was a deal breaker for me. I also didn't like the modular organization system which attaches via velcro to the inside of the bag; the pockets weren't as securely attached to the bag which makes getting things in and out of the pockets more difficult.

Patagonia: What I really liked about this bag was that the padded laptop sleeve does not touch the bottom of the bag, the sleeve was a bit bulky and was oddly attached to the inside of the bag. Also the construction of the bag didn't feel as solid.

Timbuk2 Commuter: A bigger bag than the small Timbuk2 Classic, but with more functionality. It has a cool laptop case that flips out to be TSA compliant (i.e. you don't have to take the laptop out of the bag). It also has a grab handle (yeah!) and no velcro on the flap. It was 2nd on my list, but in the end I decided it was bigger than necessary for my daily commute. The laptop case is made to fit a 15" laptop although it my 13" didn't move around too much.  I didn't like the detachable shoulder strap with swivel straps as much; I prefer the sewn in shoulder strap of the Timbuk2 Classic. However, this would be a great bag for airline travel as if gives a little more room than the Timbuk2 Classic and the TSA compliant laptop compartment.  I may end up buying this as a second bag for traveling.

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