I used to use co-poly's alot. But have not used em in a few years now. I use braid on a few rods , Big Game on a few, and fluoro on most. I just dont have a need for it anymore. Fluorocarbon was not real good or affordable years ago, but that has changed.
The 2 brands I used were YoZuri, the other Fluorclear by P Line. I really preferred the Pline. Only thing with that is I had to change it often, just didnt last long.