My view is never worry about what you need to use as its the satisfaction of both partners that matters, if your having fun and a good time and shes the same then use what ever you want!
The most i have given via intercourse alone is 7 over the course of an hour-hour and a half, of course i made her orgasm another 4 times with the vibrator when i couldn't go any longer ;P
Record for most i have given though has to be 15 in a row, i had to stop there as i was worried she was going to die her face was literally blue from holding her breath unconsciously