Oster ShedMonster De-Shedding Tool for Fine or Short Coats (Yellow)

Do you need to buy the Long hair version for a golden retriever?

I would like to use this product for my two short-haired dogs and my one short-haired kitten. Should I get the "Fine/Short Coat" or the "Cat" version?

How is this on a corgi?

Should I do the short or long for a medium length Rottweiler?