Same here, "iwconfig" is always reporting the same fixed bitrate value regardless of the real one reported by "iw dev wl3ps0 link".
Linux Mint 18 Sarah Cinnamon 64b (fresh install)
Kernel 4.4.0-34-generic x86_64 on Dell Latitude E6520 with Intel Centrino Advanced-N 6205 [Taylor Peak]
Same here, "iwconfig" is always reporting the same fixed bitrate value regardless of the real one reported by "iw dev wl3ps0 link".
Linux Mint 18 Sarah Cinnamon 64b (fresh install)
Kernel 4.4.0-34-generic x86_64 on Dell Latitude E6520 with Intel Centrino Advanced-N 6205 [Taylor Peak]