I don't have first hand experience, but a friend went out there to do a post doc.
He pretty much said that they are expected to work very long hours
Although I will say his work ethic wasn't always the best previously so that may be something to do with it
But he did say they routinely work 12 hour days and work till late at night - but still possibly should take this with a pinch of salt
hope this helps- its probably not what you want to hear, another thing to consider is that a lot of people talk about working these hours but very few do -personally i think its a case of 'mines bigger than yours'
but if you've been told you'll work these hours, then you should accept the job expecting to do so