I assume they have done some work on this road because it was not bad at all. I rode in the back of a pickup truck on a hard bedliner and had a fairly comfortable ride. We never bottomed out or had any problems. The road is narrow and if the traffic were heavy, it could get interesting but other than that it should easy for anyone with any off road experience.
The road from the Mt Massive Parking Area (East Slopes TH) to Forest Road 110J (distance of 2 miles) was slightly harder than the road all the way from Leadville mainly due to a few big potholes. From Forest Road 110J to the North Halfmoon Creek TH (a distance of .5 miles) it was a little rockier but could easily be handled by a pickup, SUV or any car with some clearance. 4WD is not necessary if conditions are dry. If your car is low clearance, you can park at the Forest Road 110J fork and walk the extra .5 miles.