Every-time.. Every time I go to Vegas my friends who have kids always drag me to this epic center of M&M's to get something for the kids back home. There are 4 floors of nothing but M&M's ahhhhh. But they always find something so the trip ends up being worth it. I even kinda like it too. If you have time you should go on the 3D M&M movie tour thing that was actually kinda coo. And I always getting a small bag of overpriced M&M's in Dark Blue.
I don't understand how Coca Cola world got 4 stars and M&M world got 31/2. M&M world is way better. One of their entire floors is just M&M NASCAR. A whole floor yeah. So if you are looking for the touristy las vegas gift for little ones I would definitely try this place.