Hey FF,
I've been taking the stuff for years, nothing but good to report (posted about it on ask curezone forum i think), I've taken high doses with no ill effects, and intend to keep taking it. Have a read:

http://users.mrbean.net.au/~wlast/msm.html

http://www.patmckay.com/Product_18.html

'MSM is a pure and beneficial form of the mineral sulphur. Sulphur is the eight most prevalent mineral in the body. MSM is a naturally occurring nutrient found in nearly all living organisms, plant, animal and human.
Foods containing sulphur include grains, legumes, fresh unprocessed vegetables like garlic, onions, cabbage, broccoli and Brussels sprouts.
MSM is also found in meat, fish, poultry, eggs and milk (milk for example contains between 2 and 6 parts per million) (1)
When we take MSM (organic sulphur) we are simply taking a mineral which should form part of our normal daily diet.
MSM is a "Sulfonyl" - Methyl-sulfonyl-methane. It is not related to the common sulphurs, sulphates, sulphites or sulphur drugs which are known to cause irritation to membranes.'

from
http://www.a1msm.co.uk/about_msm/01_what_is_msm_methylsulfonylmetha...

Mel