You have to be careful with the compressed bales becauase you feel like you aren't feeding hardly anything because the flakes are so tiny but really the flakes are full flakes. I like to feed the compressed ones to my older horse because they seem like they are easier for him to chew. They are more expensive though.
They sell them at Tractor supply, though theirs is also chopped. I also buy double compressed from my feed store, though they don't wrap it. Typically you should be feeding via the weight of hay. So the compressed bales would need to be fed less. For example, I've had bales that were hardly compressed so i'd need for feed 4-5 flakes of it, whereas I could feed 2 flakes of the double compressed.
The wrapped ones are at TC. Those are the ones I actually like to buy for my older horse because he can chew them. The regular feed stores will carry compressed bales that are not wrapped. I like them for horse shows because they are smaller and easier to fit into a space in the truck/trailer.
You pull a flake from the compressed ones just as you would a regular bale. It's just that you'll feel the need to feed more because the flakes seem so thin because they are compressed.
I used to love feeding my TB the compressed alfalfa bales from TSC, she is prone to ulcers so when she was going to be in because of bad weather the barn owner would give her some of that. Unfortunately they recently jumped in price from 12.99 up to 17.99 and I just cannot justify spending that much. I've been getting alfalfa pellets and cubes instead because they are still at 11.99-13.99 a bag.