For very small flies ( #20- #26) I prefer CDC,provided you can find feathers with barbules of a decent length. I strip two bunches of barbules from the quill,align them "butt" to "tip" and tie them in...then,they can be either clipped or pinched to size. On larger patterns,where CDC is not an option, I'll use poly,but it must be the RIGHT poly!! Some that I've used in the past is just too dense,and/or winds up kinking and curling up,after a trip or two to the water! Just the other day,the very last fly shop within 50 miles of me closed it's doors I went there two days before closing looking for some deals but everything had been pretty much cleaned out...I DID however find some stuff that looks alot like Z-Lon,only with a finer texture. It turned out to be PERFECT spinner wing material!!! Stupidly,I removed it from it's original package,to put it on a rack that I use for such things,and I believe I DISCARDED THE BAG IT CAME IN!!!! Should I be able to find it,I will let you know!!!!
PS: DID find some SA fly lines at 1/2 price,at the closeout sale!!