The big advantage of epoxy is that it will fully cure no matter where it is, and will become a very solid material once it has cured. That makes it great for joining parts that may fit perfectly together, and for joining parts where the adhesive won't be exposed to air. If you mix it right, you can be confident that you will get fully cured epoxy everywhere you put it, and all the little gaps will be filled when you're done. No other glue can do that. For gluing in tail parts, you usually need to be able to check your alignment and reposition pieces if needed. Epoxy is better than anything else in that are too since it doesn't even start to harden until the specified time.