When buying 1st year of production brings some risk- that's what the warranty is for.
New engines beside higher HP bring also better fuel economy.
I drive diesel sedans for long years and switching the same model from year 2008 to model 2014, where newer engine delivers only 10 HP less than older one, my MPG went from 27 up to 36 mpg.
When buying truck- good gas mileage is not priority, but I spend about $2300 on fuel for single trip to Alaska.
Would I drive gas engine that would make well over $3000.
You can ignore those expenses only to some point...