I've used a rattle bag to call a buck across a field. So, they must sound real enough to a deer. I've also used real antlers but the bag is easier to transport and use with 1 hand with little movement.

I use the bag. It is easier to store in times when deer suddenly appear out of nowhere.

I don't have many pet peeves, but thats one of them. Horns are on bulls, antlers are on deer. But to answer the question, real, I think they sound better in the woods.

I cant really answer the question, I always had a set of real ones, so never had to purchase any!

I use a RattleBag that a Friend made for me.
He made the interior parts of it from different sized sections of dried hardwoods that were waterproofed.
Never had a deer that did pay attention to them notice the difference...for very long anyways