Jamis bikes look like a great deal, several $100 cheaper than the 'major' brands for near identical bikes.

Don't see them here on the west coast too often. We mostly see Specialized, Trek, Giant, Cannondale, "Raleigh", Kona, and speciality brands like Santa Cruz, Electra, etc.

To me, assuming the bike is the general type you want, and you're happy with its gears and brakes and stuff, the most important thing is how well it fits you, and how in tune with its ride you feel. The different brands have slightly different base geometry... like, Specialized bikes tend to have a fairly long top tube length, which suits me as I have a long torso for my size.