What is the best year for the Ford S-Max transmission?

I have been looking to buy a used Ford S-Max but I'm not sure which year has the best transmission. I want to make sure I get one that will last and not give me any problems. Can anyone advise me on which year to look for?

I have owned a 2015 Ford S-Max for 2 years now and the transmission has been rock solid.

I have had a 2018 Ford S-Max for about a year and the transmission has been smooth and reliable.