The only problems that I have had with them involved posting of the ocassional double miles promotion. The first time I had to call them bc the window which they claimed should post past. When I called, they said they would enquire on my behalf. Low and behold, the miles posted to ua in a matter of days.
However, right now, I am also waiting for the pending posting of the double miles promo that ended July 15, 2003. I recently called, and they informed me that their records indicated that the miles were already sent to my UA account. Still no miles have posted yet, but I think it should be occurring really soon, I hope.