Joined: Nov 2007
Posts: 3,549
Likes: 1
From: Somewhere between heaven and hell
Bikes: '09 Jamis Komodo, '09 Mirraco Blend One, '08 Cervelo P2C, '08 Specialized Ruby Elite, '07 Yeti AS-R SL, '07 DMR Drone
Considering one of those is a 17" and the other is a 24 (with a 10.5" ST), it looks like you're not sure what size you need. Best to go to a bike shop and try to get fitted. It will cost a little more, but a cheap bike that doesn't fit isn't a good deal either.
FWIW, the Denver/Boulder/FoCo Craigslists offer a lot better than those two bikes you've listed. A lot of people overprice stuff, so you've got to watch out for that, but lots of nice bikes come up if you're patient. Just figure out what size you need first!