I vote for the 3pt mounted one..     just seems like  it's easier on  the tractor.   But depending on the type of tree,  you will have  branches   right up your backside too.  

I move a  bunch each Fall out of pastures and into  shelterbelts-  and  the 1-4 mile run between the locations  I'm glad I didn't go with the front mount.  It'd pound the heck of of the front axle/loader.