[beagle3]

I would expect the cost per seat (os + office at least) to be in the order of $100 if there are a lot of discounts involved, possibly as high as $400. That's a lot of money upfront.

It might not save in the support cost, I agree - but barring a (potentially uncomfortable) transition period, it shouldn't cost more either.

It is my experience (from industry) that a competent Linux admin can support about 10 times as many machines as a competent Windows admin, but only costs 2-3 times as much; However, competent linux admins are much harder to find.