I have fed optimal since it came out, I've even done growth comparisons between the 2. In my opinion Optimal is a better feed fish respond to it better and had better growth rates. I've grown some channel catfish up to 38 lbs. using the optimal hand throw feed. It was intended for my feed trained bass, but he obviously got plenty as well.
However Optimal is more expensive and not as readily available as Aquamax and you get 10 lbs. more feed with Aquamax. If Optimal could ever get their feed into feed stores at a lower price point, I think it would be a no brainer. But with them having to ship ever bag through fed ex individually it's just not cost effective.