Beside weight as island Tractor pointed out you will want to look at how much further out an attachment/bucket will be with the adapter.
I did not research it extensively because I ended up getting a Woods LC102 FEL w/QA, but I recall someone mentioning the ATI was one of the best in this regard.
I did not research it extensively because I ended up getting a Woods LC102 FEL w/QA, but I recall someone mentioning the ATI was one of the best in this regard.