We pulled off a 2-night run on the Alpine loop last weekend!!
We drove in via Mineral Creek, just 3 miles or so out of Ouray. Just off 550, up the trail between trailered rigs at the staging zone, I stopped to air down as 2 motos were decending. They stopped at my window, one with an engine skid plate bungeed to the back, and the other 'quite concerned says, "Have you been up here before?" Me: "No, not this way." He: "It gets REALLY rough..." Me: "Yeah. Thanks ... We'll be fine, we're good." He: "hmpf, okay..."

It's great having perspective. . .
We climbed Mineral Creek trail (to another similar encounter of a typically tricked Jeep spotting another heep...) Driver says to my wife (walking the trail near an obstAcle), "It just keeps getting rougher and rougher up there." Me: *thumbs up and a wave* "Cool, thanks man." We continued over Engineer pass (checking out various mining debris and historical artifacts along the route), and camped near Rose's Cabin by Hensen Creek Saturday night. Sunday we rolled eastward on the North loop through Capital City (wanted so much to see the stately Brick Mansion built by Mr. Lee) to Lake City and had pastries, then we headed towards Silverton via Cinnamon pass route (detouring up the Carson Ghost town trail to New Carson City's remaining cabins and stable). Sunday night we camped at the Mouth of American Gulch, then Monday, we visited Animas Forks and rolled out through Silverton.
I've been wanting to do the Apline loop for years and we foolishly hoped to try 7 years ago, but were ILL prepared young parents longing for camping and adventure. Fast forward, 7 'short' years, more experiences and (the right rig) we got a glimpse! Two and a half days and 2 nights is doable, but we could EASILY spend 5 days on The Loop!!!!
Again, these guides are great.
The black one (left) has LOTS of trails and basic info, the red one (center) is of a series breaking down the state into smaller areas with more trail beta for those areas and is GREAT for background info and history of the trails and sights, the one on the right is a great compendium for more historical mining and ghost town stuffs!