It is absolutely false that mealworms are bad for bearded dragons... they are one of the best supplemental feeders you can give. Mini mealworms are a great feeder for baby bearded dragons although your primary food source should still be dubias (preferably) or crickets. I remember years ago it was common rumor not to feed mealworms without pinching the heads off because "they can chew their way out of the dragon's stomach!"

Superworms are much harder to digest and I've witnessed and heard many first hand accounts of dragons throwing up after eating too many superworms in one sitting.

Instead of taking my word for it, I would recommend visiting the "Bearded Dragons and other creatures" website (The Dachiu's, introducer of the leatherback to the US) for further information or getting a copy of a good bearded dragon care book. There is a lot of misinformation on bearded dragon care on the internet (as I'm sure is the case with a lot of other species), especially care sheets on some breeders' websites .