Yeah there are definitely way better alternatives then getting CX. But I want to say with everything I have read on this site so far and my own limited experience of owning a few for a month, that it's all about management with them. You can let them live longer but you need be on top of feed management. This will be harder as I don't believe there are many sources on letting them live longer and still eating them later on. Most would probably get Freedom Rangers, Buckeyes or New Hampshires etc at that point. The next problem comes if they are on some sort of diet, they will be chronically hungry. They have been bred to be always hungry, so for welfare they need to be able to get some sort of food all the time. This is where keeping them outsides comes into play, they will be able to eat grass or bugs all the time even when not having excess to pellets etc. This exercise will also keep their leg muscles healthy and strong. But this will have the effect that their meat will be less tender cause they are using their muscles more than store bought chickens. Also there are different strains of CX. If you want a healthier version go for Hubbard or Sasso instead of Cobb or Ross, but I imagine this would be harder to find out. Although non white meat chickens will be most likely a healthier version.
As for getting attached to them, well that's indeed very easy. Although it won't just be you that gets attached to them. I have never met chickens as sweet as them. Pullets from other breeds I have bought around the same age have remained scared of me while at least one CX literally tries to jump the fence to get to me. It might be that they have just connected me with food, are simply curious or maybe they have established a deeper connection with me. Their behaviour is a bit complicated to put into words and I simply don't know how they view me.
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