What didn't you like about the taste of the CX you raised? How old were they when you butchered them, and did you let them rest for a couple of days before cooking them?
I have raised both CX as well as other hybrids -- not Freedom Rangers -- but Red Rangers and Slow White Broilers, as well as heritage, dual purpose chickens. They all tasted good to me, although the heritage had the most flavor, but were a little more firm (not chewy, but not as tender as the CX), with the RR and SWB being somewhere between the two. A lot of that flavor is a function of the age at butchering. The CX were, on average, butchered around 10 weeks of age, while the others were butchered, on average, around 15 weeks old.