I more than agree with many of the experienced participants in this lusty experience who've already posted. In short, this scenario is the source of my hottest experiences, yearnings, chat/online fun, and more. It's been a while since I've experienced one, but they have been a mixture of arousing, enlightening, clumsy, erotic, intense, confusing, liberating, nervous, mind blowing, and all else in between. In addition to the obvious variables and options physically, there are all the other things to consider that can enhance, hinder, or othewise - connection between you three, whether two are already in a relationship, interest/acceptance of voyeur roles at times, and yes, size...and more, but overall, love that lust....love it!