I've seen almost every aircraft land back gear first to evenly distribute the landing load between more struts.
However, I recently saw this video of a NASA Super Guppy Nose-Wheel land gear first at Mansfield-Lahm Regional Airport:
.I couldn't think of any reason a pilot would want to do this so is there any reason as to why they would want to land nose first opposed to the conventional way that I don't know of?