I've tried a couple of different types of generic and they seem to work as good as Dectomax. I did ask about them before I bought to see if they did work and the manager at the store said if it is made say in China or xyz country then the actual content is not tested/inspected for actual content percentages. Even though the box say a certain % of ivomec. But I gave it a shot and it seemed to be ok.
One of the p[roblems I've found with some of the egenrics is kind of like the not quite Avis commercials. The products may be as substitue for the real thing, or a generic generic. Minerqals is the one that it appears the most common in. It may have the same analysis but the type used may not be a type thayt is readily useable by the animals.
Dun- I have run into this with the mineral thing. Also, the vet was telling me he had a run recently of several dogs that were unthrifty and just generally falling apart. Some were apparently starving,even though the owners were feeding them free choice. Turned out all of them were being fed the same brand of discount store dog food. The label looked OK,but when he sent it to be analyzed,it was made of things the dog could not convert. It was all going out the back,not much left for them to live on.