I don't fly fish the fork but I use big panther martins and also curly tails. They work very well and its pretty easy to catch 30 plus nice trout in a day, especially from the Crystal River to the Colorado confluence. Most trout run from 15- 20" and there are plenty of 3 - 6 pounders.
i fished the pan wading several days a few weeks ago. did pretty well, but it was crowed even during the week and the flow was up over 300cfs but clear. i did really well on the upper pan above ruedi. the flows on the pan are now down under 200 cfs and green drakes are hatching - so it will be a busy place.
i also fished the roaring fork and colorado (drift trip) and we did very well. used a huge foam hopper (tan/yellow) with two droppers, one a tung prince nymph and the other a rusty spinner. lots of trout over 18".