I think they take out samples themselves to see how things are.
It might have been so previously, but I can't imagine that companies would allow this sort of "let the consumer find out for us" behavior in future product lines.
Remember they have several cameras behind them, so they know which parts are prone to build errors and what not. And what ever software error there might be, it will be ironed out through firmware upgrades.
If I have the money once the Mk III comes out, I wont hesitate buying it.
I bet they'll go like hot cakes and be in back order in no time...