Dimethyl sulfone (aka methylsulfonylmethane, MSM) is a volatile solid, it melts at 108C, and boils at 238 °C.
Soluble in water, ethanol, benzene, methanol and acetone, slightly soluble in ether and chloroform. There is also a note: "stink". Presumably it means just that.
Methamphetamine hydrochloride melts at 170C and boils at 212c.
Soluble in methanol, ethanol, water chloroform.. Very sparingly soluble in acetone. Insoluble in ether, benzene, hexanes.
I don't think you'd be able to tell by eyeballing crystals in a pipe over an open flame if you had MSM. If you set up a proper melting point apparatus, maybe you'd be Ok then. Anhydrous alcohol wash would remove MSM if it were present. And I would surmise that there's a distinct taste to both meth and MSM.