Im not sure how they're similar. Mitrovic scored 43 goals and Pukki 29, only 28minutes difference in play time. Furthermore Mitrovic is a legend on international level as well, record holder if my memory serves me correct. The last time I watched him he secured World cup over Ronaldo, 3rd highest goal scorer in qualifiers and 2nd most on target.
We can also add the fact Fullham didnt have a easy start playing against Liverpool and Arsenal. I say not even close buddy, not even close...
Ofcourse its not a joke, while we are at it, can you name me 4 better offensive players when it comes to heading? Its hard to compare defenders and forwards for numberous reasons so lets stick with attackers.