In NL they sell feta and next to it a product called white cheese. It's not the same and much cheaper but in [more complex] meals where the cheese is not the dominant flavor you wont notice the difference. Say a salad made of large chunks of feta, 1/4 tomatoes, q-cumber, onion, oregano, salt, black pepper, vinegar and olive oil. I would use the traditional product. If the chunks are smaller and the salad has 10 more ingredients the white cheese will do just fine.

I need to be able to tell the difference tho. My interest seem to be aligned with the producers.