In III, Donald was a lot more mature and easy-going.
In LCS, on the other hand, he was quite immature and often broke down, complaining about everything. Also the other unnecessary thing, was his fascination with the deceased. In III you never would of thought that Donald would love dead bodies so much, In LCS he is just crazy about the 'morgue party' and makes Toni steal corpses for him!
I think III's Donald Love and LCS's Donald Love are almost like 2 completely different people.