Hi,
I personally hand feed my white's (I wear gloves because I can't stand touching crickets with my bare hands).
I have found this to be a great way to monitor his food intake and making sure he is getting his vits and calcium. Then I let a couple roam his tank so he can catch on his own...
I feel that removing forgs for every feeding, into a separate container, stresses them out and causes them to eat less.

I feed my red-eye with a glass bowl. I put the dusted crickets in a glass bow (about 3" diameter and 3" tall) at the bottom of her tank. I've found that this is the best way to feed her and monitor her food intake. You could try this with your white's, but unless you can actually see the smaller one eating, it's still hard to know what he's eating....

I've heard tongs work great also, but the only time I used tongs to feed my white's, he lunged so hard on the tongs, I was afraid of injuring him, so that is why I hand feed. Also, I would use the glass bowl with my white's, but he just doesn't seem to get it!