Curry is the best player on the team with the best record and there's nothing in his stats that really is a red flag. He's got a good off the court image i would say, which seems like it would be a good tiebreaker in his favor. Hes been healthy all year and consistent. You also have to consider that he's put up those numbers when OFTEN not playing the 4th quarters. His numbers probably look even better, therefore, if you look at averages in 36 mins vs per game averages.
Westbrook missed games and he just seems like a guy who is forced to dominate the team's offense to try and keep them in games. I could maybe see him winning if he played the whole year.
Harden is a strong case but I think since Golden State has a better record, Curry seems like a better choice.
LeBron has played great but I think his time missed hurts and Golden State has a better record. LeBron might be the "true" MVP but I think Curry's case is more bulletproof.