I don't agree that they are useless or bad, but I say that with the disclaimer that they should be used only as one part of a varied diet - not a daily food item- not good for that......
Agreed. Though I only use them for certain species on occasion, due lack of availability of feeders here. I might add that I prefer, when I do use them, to firstly feed very few, and second, to feed only the palest freshly moulted ones, since the chitin shell has not yet 'set' and is soft and much more easily digested.
As a general rule when feeding anything, particularly to young/small lizards, A few more of a smaller size is better than fewer of a larger size. Small lizards can choke trying to eat larger insects than their gape accommodates.
Its commonly suggested any feeder (especially for species that swallow without any crunching or chewing) be smaller than gap between the lizards eyes.
The reasoning being that the gap between the eyes (in most species) roughly correlates to the diameter of the throat.
I feed baby mealworms to my baby chameleons as soon as they are large enough to take them. I breed my own mealworms so I have very tiny ones available when I want them and it doesn't take long before my baby chams can take them. I use them as part of a varied diet.
I don't agree that they are useless or bad, but I say that with the disclaimer that they should be used only as one part of a varied diet - not a daily food item- not good for that. For variety they are good. Ferguson bred multiple generations of panther chameleons (5 a the time of his book I think) using crickets and mealworms only and his nutritional analysis found that they provided more calcium at a better calcium to phosphorous ratio than crickets.