Dubia's cause impaction in young beardies?

We've had our bearded dragon for about a month now. Everything seems to be going fine after the initial settling in phase. Before we got our bearded dragon we purchased some tiny dubia roaches online and our little guy loves them. We made sure that the roaches we feed are smaller than the space between his eyes.

Now that we need a second batch I found a local pet store that sells dubias. When I asked to purchase them, the owner told me I shouldn't feed dubias to any bearded dragon under 8 months old. And that it was going to cause impaction. I know that advice can differ from place to place, but the consensus online seems to be that dubias are fine. Is he wrong? Are we in danger of causing our little guy impaction.

He seems to poop most every day, once a week he might go two days between poops, but never more than that. Some other things to note, he does like collard greens and blueberries. He baths every other day. Everything seems fine, but I want to double check.

Only way dubias could cause impaction is if their far too big and they have trouble eating it. However if their the right size and your beardie eats them perfectly fine its all good.

Maybe he got mixed up with superworms?

Yeah as long as you offer an appropriate size that they can easily chew up, it shouldn't be a problem at all. They are a good staple feeder. Proper heat/lighting, clean environment, and adequate hydration (usually from well hydrated bugs) all come into play as well when it comes to impaction.