No I haven't. I do use a long arm at the quilt shop, though. When the handiquilter came out, I was interested, but realized that it wasn't big enough to do large bed quilts. They may be bigger now. Grace has a standing frame that I saw demonstrated at a quilt show. The only problem I see with these is the keyhole size of a regular sewing machine. There are some machines called short arms, that have a larger throat so you can do more than one or two inches once the quilt is rolled.
Bottom line, there are too many variables for me or anyone to recommend any particular frame. It will depend what you can afford, how you plan to use it, and what sort of machine you have. My suggestion would be to see some of these in action. There is never a substitution for doing your own research. The minute you make a purchase on someone's recommendation, you will discover another product better suited to your needs. It's called Murphy's Law. :lol: