It varies from one dragon to the other. Some dragons like the pellets, and some won't touch them.
When my dragon was 5 or 6 months old I started switching him over to pellets and greens. After a while he started eating the pellets but he never really loved them. He liked greens much more. So he continued to grow, but his growth rate definately slowed down. After a few months he appeared to be really tired of pellets and he wasn't eating them anymore. I went back to crickets and veggies and he started pigging out again, and grew to 18" long and 500 grams.
This is just my experience, and you may have better luck with the pellets. But me, I prefer watching my beardie happily devour dozens of large crickets. 