You could possibly look into the "Above the Timber" map for Colorado. I found a review on Amazon.com for the Garmin 24K Topo Southwest, from a guy who lives in Colorado. He said he likes the Above the Timber better, because it shows BLM land and names of the national forest roads, while the Garmin 24K Southwest doesn't. He said that's a big deal for him because he lives in Colorado.
I debated between the Utah version of this and the Garmin 24K Southwest. I finally went with the Garmin 24K, but only because I wanted the shaded relief and more states. However, it appears unlike the Garmin 24K, Above the Timber has BLM, state lands, and labeled National Forest Service road numbers, I believe. Also, looking at screen shots of what each looks like, the Above the Timber has better contrast visibility.
Guy from Colorado's review:
http://www.amazon.com/review/R20TTN5FBBY4P0/ref=cm_cr_pr_viewpnt#R20TTN5FBBY4P0Above the Timber map for Colorado:
http://abovethetimber.com/index.php/gps-maps/states/coloradoYou can also download a free demo of Above the Timber to see what it's like. To contrast it, there's also a demo of the Garmin 24K Southwest at
http://www8.garmin.com/cgi-bin/mapgen/webmap.cgi?smap.x=329&smap.y=265&p=24051713&l=0&u=1&v=0&cp=4B21D85AFEFD585A&z=3&w=480&h=360&d=0&k=1&sc=1&rz=-2 Just zoom in to see the topo of a particular area of Colorado.