Which is best with regard to tire width.

I'm sitting here pondering tractor tires.   European tractors typically have very wide rear and front tires with very few dual tires.   But we rarely see that in the U.S.   While I know you wouldn't want wide tires for row crops what about for hay if you don't plan on using the tractor for row crops?    Would dual tires be better then a very wide rear tire?   And then wide front tires as well.   My JD 7810 has 520 wide tires on the front and duals of 480.   Each.   I like it for hay as it means less compaction.    But you sure couldn't do much row crop work with it.  

Which is best with regard to tire width.