That beardie doesn't look fat to me, he has a belly, but not much in the way of fat pads. I'd say he needs more food, but supers aren't recommended until beardies are 16 inches or more because the chitin increases the risk of impaction. Go with crickets/roaches and maybe some butter worms and silk worms. Give them more salad. Raw, grated butternut and acorn squash are always a big hit, and cactus pear, collard greens, mustard greens and dandelion greens are great to feed. Just introduce all new foods slowly so you don't give them a tummy ache.