Couldn't comment on the rear sets but a mate of mine has the stands and they are good quality. He recently bought some more components for the stands and kaneg did a great deal on price with good customer service.
Those just look like Sato knock offs for $400. The real Sato's are $500. The Vortex rearsets are $350 new. I have them on my bike and love them. I picked them up for $200 off ebay. The Vortex rearsets go further up and back than the others.