Chidori/Raikiri vs "Lightning Chakra Envelopment"

Is Chidori/Raikiri an overkill, chakra-wise? If we look at Cloud ninja who frequently use lightning chakra to envelope their hand or tools (e.g. Raikage when he chops off his left hand, C when he uses a lightning shuriken to slice Killer Bee's sword) it seems like they do this more chakra-efficient than when Sasuke/Kakashi use their Chidori/Raikiri. It looks like they do this with ease as opposed to Sasuke/Kakashi, whose jutsu drain their chakra (except for the last arc lol plot).

Is there a clear advantage to the Chidori/Raikiri that the "lightning chakra envelopment" doesn't have? Both techniques seem potent enough in killing other individuals, but it seems like "lightning chakra envelopment" requires less chakra.