The Colorado is our best trout river. From Kremmling to Dotsero it offers great fishing for rainbows and browns, with some over 20". Bait, lures, and flies all work well.
However the best fishing on the Colorado is from Grizzly Creek in Glenwood Canyon to Rifle. I have caught 8 rainbows over 10 pounds in the last five years in this reach, mostly drifting worms.
Below Glenwood has probably the biggest rainbows in the state. Almost all wild fish too.
The C in that area is fishing well right now. The flows are abnormally high for this time of year due to realeases out of Green Mtn. Res., but the fishing has been great. We had significant rain on Tuesday night which colored up the water pretty good. Give it a couple of days to clear up and your are in business. Streamer fishing will be prime right now, but fish are being taken on dries (blue winged olives, red quills), but you can catch fish on almost anything. This is a great time of year to fish the lower river down near Glenwood as mentioned above. I would agree that area holds some grande fish. Good Luck!