I am re-joining the Hellcat club and this site. I sold my Hellcat a couple of years ago and fell into bad company with another Corvette. Now have now regained my good senses and have a Redeye in the works. An old guy cannot get in and out of a Corvette anyway. JBS$
IMO, look for a '17-'18. The '15-'16 are nice for what they are, but Dodge ironed out the teething problems mostly by the '17 model year. I'd say the best ones to buy are the '19-'20, but there's a pretty big price difference on the secondary market for those. The 17 is just right IMO.