My guys eat Dubia, which are much the same. Great feeder, but I've found that it can take a little while to get horned frogs to eat roaches... If the frog is healthy and fat, just skip a feeding or two, and then offer the roaches - hungry frogs are less picky! Also, the freshly molted roaches are soft and seem to be more readily accepted...

An alternate feeder that has a great calcium to phosphorus ratio, no impaction risk, no parasite issues, low in fat, and cheap is the nightcrawler. Horned frogs seem to really like them. If I'm dusting, I dust about a third of the nightcrawler (head end) and feed that end first. I feed my horned frogs mostly nightcrawlers and Dubia, and the (very) occasional mouse as a treat...