Hest: I'm the opposite - phys chem is my strong point.
"From my practical eksp. the usual wathercontent in methanol (when used as an azeotrop) is 3-5%"
I assume you meant EtOH ?
AFAIK the market for toluene/benzene goes through phases. Sometimes benzene is the more valuable product, sometimes it's toluene and plant production is adjusted accordingly. This may have some influence on which compound to use for dehydrating EtOH industrially.
These days Benzene is used less due to its toxicity, being replaced with Cyclohexane, Toluene and more recently, Propylene Glycol.