Ghann's has a much better reputation than wormman. Try typing "wormman" into the search and see all the complaints that have been popping up in the last couple months. I've never seen a complaint about Ghann's.
Mealworms really aren't good for for dragons, they have a low meat-to-shell ratio, so your dragon has a hard time digesting them and then gets almost no nutrition for it, plus in smaller dragons there's an impaction risk. Superworms have much thinner shells and are better, but still shouldn't be given to small (under 16") dragons. I think you should just forgo the whole jar idea, in order to get a single worm out you'd have to dump the whole jar. I keep mine in a $.50 tote from walmart with holes poked in the lid. Works just fine and didn't cost much of anything, and I don't have to disturb the entire tub to remove a few supers.