Simplest is, if you can't see the meat before its cooked. Just don't.

Other wagyu stuff that don't make sense is burger and pizza. A wagyu patty isn't going to benefit that much more than normal beef. Likewise with pizza, its going to be burnt in the oven anyway, you lose all the benefit of it being wagyu.
If you eat, you can tell the difference immediately. I find the meltique beef has a weird taste. Fat injection can't even make it taste like a good marbling on normal beef, won't even come close to a wagyu.