I agree with most all of the others. Superworms are often a bit controversial, but I think it is widely accepted that they are not good as a sole feeder. When mixed with a varied diet, they are fine. Taterbug, Jess, and SHBailey are all very knowledgeable so I would take their advice.
Beardies often require some time to adjust to a new setting (even as adults). How recently did you get him? Is he eating veggies? Around one year of age (it varies) beardies generally start to slow down on insects and switch over to a diet with more veggies. It could be either this or adjustment. If he isn't eating veggies either and this continues for awhile, I would reccomend a vet visit. Various things, parasites for example, can affect diets. In fact, a general vet checkup and stool test are a good idea for a newly acquired beardie.
Darcy- Why would you choose to feed a higher fat diet? As earlier stated supers are fine in a varied diet but not great as a staple insect. Silkworms are actually one of the best feeders out there, albeit a bit pricey.
I haven't fed hornworms but I was under the impression that they are fine and great hydrates. Is this the case?