Mayo doesn't have as much taste, IMO. I prefer Miracle Whip on sandwiches.
Some of the comments are funny. I was a little surprised that the poll tips heavily to mayo. I'm glad a couple were in my camp and I felt like I'd entered some alternate universe. I would eat mayo on a BLT but I just prefer MW. With LOTS of MW lol. Sometimes I put it on both pieces of the toast! No, mayo is just plain bland but not unpleasant. It's better for certain other things I make and for most of my versions of potato salad, I use half MW and half mayo. And usually a big dollop of yellow mustard. I make it about 3 or 4 different ways now. And people always are crazy about it. Well, no, it's my 3 mustard one that is the most popular now.
Now get yourselves some Boetje's German mustard and learn to like it. I love that stuff since I was a kid. Black rye, Swiss cheese, Boetje's, on brats, on burgers when I'm in the mood, In one version of potato salad. There's another brand that's almost as good, think it's Roenfelt's or something like that. Maybe that's horseradish. I use that to make my own Shrimp sauce, Heinz chili sauce (no other brand will do), ketchup in a pinch, fresh horseradish (keeps pretty long in the fridge) and some lemon juice.