The overwhelming preference among all the modelers I know is the JB Weld. They all swear by it. I was using the 30-minute epoxy, and had no problems to speak of, but I wanted to see what the fuss was all about. I bought a pack of JB and on the next model I made my linkages using the JB Weld, and I could tell that it would do a better job just from using it and watching how it coated, how it adhered to the stainless end and the carbon fiber shaft. After several models, my vote is for JB Weld. Also, I found it to be neater overall and easier to clean up than the epoxy, and mixing the portions was much easier, because you can be more precise with the JB. Less waste, for sure.
~ Jim ~