Average size is plenty enough. Be prepared to work....directing most of it to her. Take your time and warm her up slowly before you penetrate. If you should ejaculate early, wait and go around again. (The total time could be an hour or more.) Don't forget the lubrication..... proper lube (condom friendly if used) will add to the pleasure of both of you in foreplay and make a super tight seal during intercourse. Keep tissues handy.