I rode about a week ago--5'4, size 26/28, "tree trunk" legs. I'm still roughly the same size as I am in the picture below, to give you an idea. I rode with my friend who is also plus-sized, her legs are slimmer, but hips are wider or as wide as mine. After reading this thread, I was terrified I wouldn't fit.
We fit with absolutely no problem in the car together (and I very bluntly asked the attendant if we would fit in a car together), but it was a TIGHT squeeze on my legs--pulled the bar down no problem, still locked even at a higher point, but my legs were completely immobilized and wedged in--made for a rough trip on the turns, but since it was short, it wasn't the end of the world. I don't think I'd have done it again this trip, but I'm inspired to work a little harder to lose weight for next year.