I've had my horses on MVP Exceed 6 way. Love it for one, the other 3, I haven't noticed any difference one way or the other. 

I'm getting low in stock and wondering if there is something else out there that is more cost effective? 

The mare that I noticed a difference in  is 17 and has some stifle issues. I purchased her back (sold her 4 years ago) last summer, lame. They had given her 3 weeks off with no change. I started her on MVP as well as a monthly dose of polyglycan and she came back sound and strong after about a month and a half.

Just curious as to what other people are feeding as this is sinking my Titanic. 

Mine are on horseguard mega dose. Super jam packed with everything they need and very reasonable price wise. I want to say 48.00 for 2 month supply. 

I would keep the 17 year old mare on the MVP Exceed 6 way since you know for a fact that the Exceed 6 way is making a difference in her, the other 2 I would look into the MVP Mega-Cell or the Mega-Mag, these two are a Multi-Vitamin Mineral supplement with Amino Acid. I have learned over the years to just stay with MVP, they are so reasonable in price and proved to work in more cases then other supplements out there, its so overwhelming to me to try to shop for supplements, way to many out there now adays to try to choose from , lol..