I've had very good results with ground up alfalfa pellets (guniea pig food, for added vitamins).
I think I'm going to look into getting somethign cheaper - chick starter maybe - as the number of roaches I now have is increasing to such a degree that simply maintaining the colony is going to be expensive.
My advice is start now, with as many as you can afford, and plan on not using any (except for a few spare males as treats) for 6 months or more. You'll be happy.
I use them for the melleri and deremensis. My veileds dont' seem to like them as much. They like to eat things crawling in their cages, and I will nto allow a roach to crawl anywhere unsupervised. I must be present at all roach executions, for fear that one should escape.
Spare males are for hand feeding, not bowl feeding, as they could fly. I tend to use large nympths for feeding - they seem meatier than adult males (guess so much goes into their wing formation). Plus, they're a better size than the big females (thoguh I must admit melleri do love a massive female roach here and there).
I'm at the stage where my cricket usage could go down by 80-90%. I'm going to hold off though, and just let them grow out a bit more.
Dubia are hands down the best insect I've used. They are easier to contain than crickets, they don't stink, they are easier to breed than anything else I've tried (leave them alone and it happens)... the young are small enough for very young chameleons (but not for babies), while the adults are perfect for the largest chameleons - you wouldn't want a larger size feeder. They're meaty, and easy to feed. Unlike orange headed roaches, they don't kill each other... much.
and they are tough. They won't breed if they get out (I am pretty sure they won't- I had to increase the temps to get them to breed a lot.), and they can live through cold spells better than most other roaches. I recieved them via USPS i nthe winter, and they were all alive despite being on th eroad for 4-5 days.
And they do not stink - that's a bigger plus than any of them, worth repeating.