A few times...
First time, I volunteered to crossdress at a charity event [Little did they know I'd love it!]...My gf at the time, who didn't know I dressed joked that she would, "Have her way with me" that night after the event. The joking led to more joking and a dare or two...She said, "I'm serious, I'm going to buy a strap on" and I said, "Go Ahead".
Well, of course she did...When the fundraiser was over we went home and I stayed in my femme outfit..Oh God, did we go at it all night. That was my first time being pegged, though I'd used dildos on myself. Being laid by a strap on was MUCH better!
Second time, was a gf who uncovered my love for Tgirls by looking though my browser history. She was a very horny woman and very open sexually, late one night she came to my place and under her dress she had on a strap on...She made me suck it and then she lubed me up and went to town. Funny thing is, I never told her I crossdressed and never got the chance to with her, as we broke up shortly thereafter.
Third time, I had another nympho type gf, she knew I crossdressed. We had threesomes, foursomes and moresomes together. We made an elaborate plan for her to use a strap on on me one night while I was all dolled up...that time led to many times...But, it wasn't as hot as when we got to enjoy men together!
WOW, not only does this sound really hot, but you were really lucky to experience it with three different women.
Most men can't even seem to fine one!