The initial climb out of the parking lot is by far the hardest part of this section of the Colorado Trail. Within the past several years, a re-routed portion of trail was created and if you carry a map with you, it might show the trail going northwest, instead of the correct southwest. However, the trail is very well marked and easy to follow. Once the initial mile or so of climbing on pea gravel is out of the way, the degree of steepness does ease up somewhat, although this trail continues gradually upward for many more miles. While we were prepared to do some climbing, this section of the CT really kept it coming.
Luckily, the grade is never too steep so that you should be able to grind up most of this trail. The first 1/3 of this trail is burned out from a recent forest fire, and is quite interesting to ride through. The second 1/3 of the trail is normal forest, while the last 1/3 is back in the burn zone (you will cross a fire road at one point, and although the trail has no markers on the other side, you DO want to cross the road and continue on the singletrack). The last 1/3 is definitely more level, although you will encounter a variety of ups and downs and at times, some very fast singletrack! The final mile from Hwy 126 to the Little Scraggy Trailhead (where many park for rides into Buffalo Creek area) is nice and flat doubletrack.
The trip back from Little Scraggy is where this section of trail really shines. On the return, your first 1/3 is fun ups and downs, the middle 1/3 has one short uphill section which will be the last of the climbing for the day...and the last 1/3 is pure downhill for what seems like forever! This is payback for all the climbing you had to do on the way in... None of this trail is particularly technical, and most of it is well traveled and well worn. Naturally you can get some pretty good speed going since your visibility in the burn zone is fairly distant.
You will need to bring as much water as you can, especially in the summer months, as there are no water sources on this section of trail. If all goes wrong, you can bail out on Hwy 126 and head down the hill back to the "town" of Buffalo Creek (and take the gravel road back to your car). If you have a water filter, you can water up at that point. However, all effort should be made to ride this trail in both directions, as the return back down the hill is really worthwhile. Set aside 3-4 hours to do the entire route. More if you like to stop, enjoy the scenery, etc.