All depends how much you drink, I've read of a guy telling stories about how bad they are... but when you read closer he drank 2.5 full sized wine bottles. over a 2 hour period (actually he and his brother drank 5, since he can't remember oppening the third bottle it is had to say who had exactly how much.)
It is also important to remember that alchohol dehydrates you... I always drink a lot of water, when i drink alchohol I've never realy had a hangover... I used to drink 750 ml bottles of mead in my first batch... But that was more alchohol than I needed at one time so I went to bottling in 375 ml splits with a few bigger bottles for parties. Usually I only drink 1 split, though when i have company I only drink 1/2 of a split or so.