I'm not quite at 11 gpp with my Kanati, 10.32 gpp, but I got an average of 175 fps with it the other day. I thought that was great for a 46# bow and 10+ gpp. The Kanati has Actionboo limbs under clear glass. I think limb material can make quite a difference as can limb design.
Your 171 fps sounds pretty darn good to me. I always thought the Kanati was pretty quick. Now that I have a chronograph, I have confirmed that. I was drawing 28" and using a cordovan tab, but my shots were very consistent speed-wise. In fact, when I shot my RER XR, I think the first three shots were exactly the same speed, and it never varied more than 2 fps.
My first couple of shots with the Kanati were 171 fps, but I hadn't warmed up at all first, so I probably drew short on those. Once I warmed up, the shots were again within 2 fps.