I haven't had them on an R6, but on a GSXR they are the bees knees. The only bad side about them is that they will chew the crap out of boots because they have so much grip. As for GP shifting, you will still need to get a new shift rod due to the design of the R6 frame.
Yeah I agree with Chango, I bet they chew up boots and I bet they hurt too if someone's walking by and catches a shin to the peg. Have you looked into Gilles Tooling, Harris Performance, or Graves? They have nice rear sets, and your getting a nicer product paying a hundred more than Vortex.