My experience was a long time ago. For me, the idea of it was hotter than actually doing it. I think that is why some of the guys mentioned in this thread came so fast... the build is intense, but for me, I felt like we needed an air traffic controller to keep things moving along
I don't want this to sound rude, but the M of the couple I was with needed to be a little bigger for it to work well for us. The best position we found was with one of the guys on their back at the edge of the bed. His wife was laid back on the guy's chest lying down (reverse cowgirl), and the other guy stood and did his thing. The guy on the bottom and the woman had to stay pretty much still, or it was like a can of snakes.