I know others will answer your question a lot better, but here's just one example of a difference. The wheeled helo can taxi better. One flight I did with my dad in the Huey he was flying, he was asked to come to a pretty confined area to get to the avionics hangar we were going to. Lots of light aircraft around, and he was very, very heavy so he didn't want to load up the rotors by hover taxiing. So he taxied with the skids dragging a bit, enough to move easily but not having to fully load the rotors which may have flipped or damaged nearby fixed wings. Makes a helluva lot of noise too. And I would just guess that would be more important when you get to some of the larger helo's that are wheeled such as the Sea Stallions, Sea Kings and Chinooks not to mention the huge Russian beasts (Mi-6/26).
Good question though.
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