I would like to start my 6 y.o. on a preventative joint supplement because of his conformation. I am looking for something preferably pelleted, although I can deal with powder, and relatively inexpensive, but effective. I was considering SmartFlex I Maintenance, but I don't like that it doesn't have Condroitin Sulfate in it. Does anyone have any experience with this supplement? I recently started my 20 y.o. on SmartFlex Sr. but it's only been 2 weeks so I can't really tell if it's working yet. I'm trying to get all the horses in my barn on SmartPaks cause they're so much easier. Does anybody have any suggestions for a good preventative joint supplement other than SmartFlex I?