Very nice road, though usually clogged with four wheelers. Avoid rush hour (plenty of Boulder workers live in Nederland) and try for mid-day during the week, not weekends. Who knows, though? It's a crap shoot what kind of traffic you'll encounter. There are some side roads worth noting: Four Mile Canyon up to Gold Hill is a very nice ride. Likewise Magnolia Rd.(turns gravel before you reach Peak to Peak Hwy. south of Nederland.) Sugarloaf Rd. is great: it starts paved and eventually turns gravel, but the scenery is great. Roads like this are why Boulder is heaven for bikers.
Living in Denver, I can ride this route 6-8 times a year. Can be crowded with hikers, tubers, rock climbers and gawkers, with their cars parked in the turnouts, so be careful. Nice curves. Well worth the ride.
A wickedly twisty 20 mile section of curves leading down to the lake at Nederland. Try not to get distracted by the climbers on the steep granite faces!