I use them here as well. I've use their Shine ones, MSM, SmartDigest for my older horses, red salt, and source. I've used their SmartCalm too and I'm probably going to put my horse back on it. He seems edgy again and I thought that the supplements weren't working well, but now that he's been off of them for a month, I'm seeing the difference.
I also like that if they don't work, then we can get a refund, but I have yet to actually use it because things are working. That makes it so much easier to want to try something new. Also I just buy in bulk containers. I'm a stay at home mom and my barn is in my backyard and with four horses it can get pricey.