Superworms are great for beardies over 16" in length. Babies have a kink in their intestines and it can be hard for them to pass superworms. When they get older/larger the kink straightens some and they don't have the risk of impaction.
I'm not sure what a finial is so I need to look that up, unless someone else can help out with that question.
We feed our beardies a varied diet of Repti-worms (the black soldier fly larvae), crickets, silkworms and the occasional waxworm. I just ordered 100 butterworms from Mulberry Farms so hopefully they will like that also. Have you tried any of these soft-bodied worms?