FWIW, I've always considered the Brain Bag to be too large for me. I'm in the same category as Just and Shiva -- female, and under 5'4" in height. I also have a Smart Alec. The thing about the Tri-Star, is that if you don't need the extra space, the compression straps on the inside cut down on the volume. And it's really when I need to fit in oddly sized objects that the Tri-Star design becomes useful -- not when I'm loading up on weight and trying to overstuff the bag. Another thing is that with the Synapse+Tri-Star combination, I'm not carrying the Tri-Star backpack style, but with the Absolute Strap. It's probably not as much a factor if you're taller -- backpack has some extra inches on me. However, you'll find a number of threads in the forum by various women about when the Brain Bag is considered too large for them, including some people who tried ordering, took pictures with the bag on their backs to show why they thought it was too big for them, and then sent the bag back.
Originally Posted by Carolina
This is probably a personal assessment, so YMMV. This is just what works for me.