The 30 is quite spacious. I filled it up quite easily with a wide range of equipment without even filling the upper compartment. The downside is that it is large (about the same size the as R-103), and my wife indicates she will not wear it. (We like to shift the load back and forth at times.)
What fit in the bottom compartment of the 30 (with some more room to spare)?
* 40D with 70-200 L f/4 IS mounted (with room for longer lens)
* Canon 100mm macro
* Sigma 18-200 OS
* Two boxed 77mm filters
* The Kata Weather Cover
* Canon 580 EX II in case
* Canon 450D with Canon 10-22 mounted
* Tamron 1.4x Teleconverter
* Tamron 2x Teleconverter
I actually prefer the 30 over the R-103, except for the fact that the 30 (or 20) cannot accomodate a laptop or magazines, making them less useful as a single carry-on on a plane. (Anyone want an R-103?!).
So, my wife and I are torn between keeping the 20 or the 30. I want a bag that she will be comfortable wearing while wondering places like Disney World, which the 20 would do. I also do not want to carry multiple camera bags on trips, which the 30 would prevent. I have a feeling I will go with the 30 and cram a smaller bag-only (no gear) into the luggage.
Again, one other drawback is that neither bag works as an all-in-one (just 3N1 - get it!), handling camera gear and computer/mags/docs. The best solution there is the DR-465 - which is too big for parks and requires dismounting to get to gear.
Some other things I haven't mentioned yet:
1. Why won't kata put water bottle pockets on their bags?!!!
2. The 3N1's have an added benefit of acting as a stable base to rest your arms when taking a picture. This was an unexpected benefit.
3. Another drawback to the R-103 is the shape of the bag, including the shape, configuration, and accessiblility of the few pockets it has. (And nowhere for a water bottle!)
4. Another reviewer mentioned the zippers being awkward on the 3N1's. They are. But livable. I understand the challenges they faced and the design decisions they made. I'm ok with it.
5. Another reviewer mentioned that the upper and lower compartments of the 3N1's are separated by a zipper, and therefore not safe for keeping wetness from moving between the compartments. This is true. It does make the bags more flexible, but less useful, if that makes sense! (Of course, if you could easily put your water bottle on the outside...
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6. Kata did not put any straps on the bottom of the bag for attaching a tripod (like a Gorilla Pod, which would be a nice fit). I'd prefer not to put the Gorilla in the top, as it takes a lot of awkward space up. In fact, except for one d-ring on the face, there are no means to attach anything to the bag.
7. There are 2 side pockets by the upper compartment. They seem like they should be handy, but note that their space is carved out of the upper compartment - so they can "interact" with the items there and take away from the larger compartment's volume.
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