Has anyone ever used the Chopped Hay in a Bag?  

I have used it on occasion. Mainly the alfalfa.

I had to use it for 3 weeks as a step to wean my horse back onto hay after a hay elimination diet. It's really fine and powdery. I used the Standlee chopped alfalfa. Its more like powder really with some 1" or so pieces. 

Ive used the Triple Crown brand to help slow down my gobbler. Just threw 2 handfulls or so into his feed and it helped a lot!