I'm personally all about splitting a fifth with a girl 3/4, 1/4. Haven't done it in a while due to the old lady but it used to turn out good.
As for volume, the only time I kept track was last st patty's day 12 irish car bombs and an adios motherfucker and a half (breazewell couldn't finish)It goes black for me here. I guess I hit a judo roll out of a moving car at four in the morning and resurfaced the next day. But it was a 12 hour marathon.
What is that like four bottles of tequilla.....