Nonsense.

I've worked with several venture funded startups, all entirely satisfying experiences, and twice for large corporations. The big places were both good for the first six months, and then you ask yourself repeatedly 'what kind of fucken life is this?'

edit: important to note, the caliber of the founders is key. if they have done this before, or if they've held senior positions at large organizations before, then it's a good bet.