I also agree with BrianI and rfordut, as a 6'1" person who's not especially heavy, but certainly not thin, the synapse looks too small on me. I live in Seattle, so I've tried it on at the store multiple times. Everybody here seems to loooooovvvve their synapse, so I keep thinking "maybe it will look different this time", but alas. I'm eagerly awaiting the larger version, but for now I carry the SA every day I leave the house for work (mostly I telecommute). Also it is my general hold everything bag for doing things with my almost 3 year old. Remove the brain cell, add snacks, extra clothes, discarded coats when we get inside, water bottle, hat, umbrella, etc. But since I started waiting for the diaper bag before my wife actually got pregnant and we still haven't seen that, I don't think I'm going to hold my breath for the larger synapse. :-)
My SA is black/steel/solar, which I got not too long before they discontinued solar. It is the old style, and I've been tempted by the spiffy new features, but the lack of solar has so far been a deal breaker for me. If need be I can fit my personal 15"MBP in a brainCell, my work 15" Dell in a cache (got to have your priorities) plus both power supplies, cube with cables, mouse, usb drive, etc, JamBox, insulated KleanKanteen, umbrella (in pocket with KleanKanteen) pens, assorted bits and bobs, and still have a little room if I need to add something small. But when I don't stuff it it is even nicer to carry.