Well, the shaft is better, IMHO, in the HB CP2 since you do not have to pull the shaft out of the bottom to replace it. On the BCP, the shaft HAS to come out of the bottom, and you may have to straighten the shaft some BEFORE you can pull it out, since the bent part has to go through the frame.

I won't say it is a harder material, because I have bent mine [&o] but it was much easier to deal with since I could pull the shaft out of the top. I did not even disconnect any linkages, I dropped the shaft far enough to remove the head from the shaft, pushed to head to the side slightly, then pushed the shaft up out of the frame and swashplate. I was able to straighten it enough to reuse it, reinstalled it, and was back flying in about 30 minutes.

I don't know about the electronics, since I have only seen the E-Flite electronics.

The only complaint that I have about the HB CP2 is a slight amount of play in the paddle control frame pushrods. It still is more responsive than the BCP, though.