No, they haven't cracked. One of them, only one, bent permanently, but the others are fine.
I've seen those disneyshopping ones at the store, and they look tacky *to me*. Plus they aren't connected with Disneyland, just Disney, and the Disneyland connection seems to be what's important for DS. He likes the things he got at the parks MUCH better than things I've ordered online for him.
And I find it to feel very wasteful to just toss the plates away at the parks, so even if they only lasted one meal I would feel fine with it. The fact that some have lasted over a year is an extra extra extra extra bonus.
I even once cleaned off a plastic plate/platter from Rancho, that hubby and my shared enchilada meal came on, because it felt so WRONG to throw it out. But that did crack, it's a much harder plastic than the kid's meals Mickey plates, so I don't do that anymore.