I recently wrote up my (admittedly a bit rudimentary) tutorial about my dubia colony HERE
@ashleyraeanne is 100% correct- mealworms are not acceptable as a diet staple, and a terrible idea as the sole diet item. They are worse than McDonalds- it’s like feeding human beings solid lard. While this does occur in some (human) cultures, it never composes the entirety of the diet. I have seen quality data comparing Ca:P ratios, fat content, moisture, protein, etc. with that of other feeders, but I’m not able to look up the references right this moment- I’ll try and remember to elaborate in a subsequent post with references.
But the very, very short version, is that BSFL are the most inherently balanced feeder for most purposes and the only one I’ve heard of that can be used without gut loading/supplementation. Other feeders can be quality nutrition with gut loading +/- judicious supplementation. I personally feed my adults primarily hornworms, dubia, BSFL, and occasional silkworms and Leopa gel. I keep superworms, butter worms, and mealworms as backup emergency snacks. Uh… snacks for my geckos, not me. 
(edit to fix autocorrect)