I shy away from too much pellet food. It was my mud turtle who ended up with problems (bladder stones) and the vets all determined that I needed to stop feeding him so much pellet food.
So since that happened in 1997 he's been getting a very wide variety of live foods, frozen but thawed out for him fish foods such as bloodworms, brine shrimp and other animal types of fish foods that don't have a lot of additives. Live roaches, worms, crickets, and fish are all foods he loves.
He does get some pellet food but only about 2-4 times a month.
The stones have never come back so far, he'll be 10 years old soon.
He won't eat the Mazuri pellets, he won't eat the Zoo Med either but that's him being picky. I wouldn't choose one pellet over the other, I just try to feed the most natural diet that I can.
This is just my 2 cents. 
-----
PHRatz