The Hart and Lindsay measure two separate things so you can't say one's more accurate than the other. The Hart is awarded to the player judged to be the most valuable to his team. The Lindsay is awarded to the most outstanding player as voted on by his peers.
It is entirely possible for Taylor Hall to be the most valuable player to his team, and McDavid to be the most outstanding player.
Now, if I was a player, I think I'd feel much more accomplished winning the Smythe, then Lindsay, then Hart. Smythe 99% means my team won the cup, Lindsay means regardless of what happened I was the best in the league, Hart means that I committed more to my teams success than any other player in the regular season, however, that could mean dragging a team who doesn't belong in the playoffs to a first round exit.