I've helped organize a few stag parties where pegging between girls was a big part of the show that seemed to generate good tips...but the quality of the toy matters. I usually borrow Chloe's well appointed toy bag, but was unable to coordinate it for a party earlier this year. Ended up with a super cheapie thing picked up last minute that was just not the same...lol!
There is one variation I highly recommend that I tried at a swinger party several years ago. While one girl is doing the other in standing doggie, get underneath and use a digit or two to massage the G-spot of the girl pitching (wielding the strap on) as she goes to town. Greatly increases the fun for her...particularly if she is a squirter.
I confess that for all the fun, having to scrub and sanitize a bunch of fake phalli (correct plural of phallus?) is not my idea of fun...