First of all, Carisoprodol(Soma) isn't really recreational for me. It can have a minor relaxation effect, like 0.5mg alprazolam. I took 2 tablets (700 mg), then took some MXE a couple of hours later. As the MXE kicked in, I had completely forgotten I had taken the Soma. I noticed I seemed to have much better than normal balance and coordination(It was late at night and I was walking quietly and carefully to avoid making noise). It was remarkable how easy and effortless this was, I felt cat-like in my nimbleness and stealth. It was only the next day that I remembered taking the Soma. I figure that had to be it, although I haven't tried it again.
So for me the combo was good. I don't think it would help me fall asleep, but I have a small benzo tolerance. Zolpidem( chewed up and absorbed sublingually for ten minutes before swallowing)always works for me.