I've used them for years, and buy them at a feed store. They are a good fertilizer, but more than anything, I think they feed the earthworms, which makes the soil way better, in my opinion. When we moved here a few months ago, I found maybe one or two worms in the garden. When I planted all of my daylilies, I put a handful of alfalfa pellets in each hole, and then spread some around each plant. When I later planted more daylilies, I found way more worms.
I paid less than $10 for a 50 pound bag of pellets. Make sure you get the ones for horses. I think someone said that they are cleaner than the rabbit pellets, but it may have been some other reason.
They are easy to use, smell good, and the daylilies and earthworms like them!