I not only have one - but I have two!! I had two older Pfaffs (2170 and 2058) for many years and the DH purchased one for me one Christmas. It fit both machines and I just Loved it. I sold the 2170 because I found a newer and larger hoop Pfaff - Creative Performance - but the foot print and arm shape were different so the Sew Steady did not fit. Santa brought me a newer table that next Christmas.
They are pricey but imho well worth it. I still use the older one with the 2058 which I kept for retreats. It looks just about brand new. They both came with a carrying case. Mine are the larger size. - there are four height adjustable feet fixed at the four corners with another adjustable foot with a suction cup on the top that you can place in the middle of the back. The feet come off easily for transportation. I am currently doing "small quilts" so a 1" finished square needs to be 1" so one feature I really like on mine is that there is a "ruler" printed on the front piece which I often use when something looks wonky (not that that would ever happen lol). I just hold the piece under the table and can slide the piece around to check on that perfect 1" square!!
I am sure that there are lots of other brands out there now - but these that I have are well made, a hefty piece of acrylic that does not bend, the surface has stayed pristine and easily adjustable (my machine is on a large heavy plastic folding table and is not particularly uniformly flat). I would not hesitate recommending it to any one.