They can but I wouldn't go past a hopper just b/c adult mice fight back & can bite pretty hard. I used to have a full grown female beardie who was huge & she ate hoppers when I felt like giving her a treat.
you might not want to feed him too many pinkies.... they are way too much protien. it would be like you eating a rare staek for dinner every night. its just too much. your beardie can divelope the reptile form of kidney stone and gull stones. over 500 adults and we dont feed a single dragon pinkies just because of that risk. if you do dicide to keep feeding them i would have to absolutly agree with what nigel, lena, and jason.