It highly depends on your playstyle, but I tried to generalize as much as possible; Reference is having played many years of Pokémon myself.
Say you want to have the best chances in lategame, whereas lategame I refer to when everbody is lvl 30+ and eventually battles between players is implemented, you should go with the one on the right (higher iv) as until then you should probably have it maxed out in terms of cp.
If you're just happy to have a strong dragonite and you don't care too much about being the best/ part of the betters, you can go with the one on the left as it certainly is also a strong pokemon.
Long terms short: Some people still don't have a dragonite so at the moment you're still at a very good position, but in say a month more people will have a dragonite and eventually the individual values iv will start to matter more.