Do you want to make money?
Then go for the position at the fast paced club. As a barback it's your work
ethic that will determine how good you are. I've seen dumb as a box of rocks
types without any experience who turned out to be great barbacks because they
had the drive to get the job done. Also I've seen some rather intelligent
people who couldn't muster it because they were ummm... Lazy... they would
rather flirt with the customers than get their job done. Don't worry about
people skills as a barback. Its the bartenders job to interact with the
customers. Don't be intimidated by how busy a place is. The busier the place
the more barbacks there will be who will help you. Also any halfway decent
bartender will teach you how to get your job done properly so he/she gets
their job done properly.