I will always have an affinity for G1 Megs because I grew up with him, but he's been so many things since the last time he was a gun, I'm not even that excited that he's about to be a gun again in the new classics line - but that's due in no small part to the fact that he's going to have to look like a Supersoaker to pass safety laws...
Off the top of my head, Megs has been a green alligator, a purple alligator, three or four different kinds of tanks, several different types of jets, a sports car, a t-rex, a mechanical t-rex, a dragon, a giant hand (LOL) and most recently, he's been doing a stunning imitation of the Batmobile. Considering all this, I've found myself very receptive to new Alt modes for him. Cybertron Megs is my favorite in a long time, though.