Sol, my container of MSM from the feed store says the only ingredient is MSM 
(no fillers or other compounds which are found in capsules and tablets).  The 
DMSO is 99% pure which may or may not be the same quality as one can purchase 
at the health food stores.  Have used both for a couple of years when I found 
out I could get so much more for my money at the feed store.  The MSM dissolves 
very quickly in water and when a capsule is opened and poured into a glass of 
water, it never completely dissolves.  This is certainly not scientific 
evidence, just anecdotal.