Dragons get bored with the same live food all the time. I can't imagine they would be happy eating only prepared food. However it would be convienient to have him willing to eat prepared food occasionally. Some days I need to be able to just pour something in everyone's dish and run. Bogie insists on live food and salad. Spoiled dragon. At least I don't have to hand feed.
Variety is the key, they will get spoiled so easily. If you start with variety they will accept new and different readily. Check out the Beautiful dragons feeding chart. It's the best one I have found.
Good luck.
The little information I have found is in dragons that end up being smaller "and probably not as healthy" as dragons that get a proper diet and supplements. I know many people that buy packaged food end up using it to feed crickets or roaches.