In our first wireless throughput test (the 2.4 GHz band at 20 MHz width), we have the AirStation starting out around 80 mbps, and topping out near 112 mbps.
Increasing the channel width to 40 MHz had the Buffalo starting around 80 mbps once again, but topping at 180 mbps towards the end of the run.
Moving to the 5 GHz band at the 20 MHz channel width, we find all routers tangling up. Peak rate for the Buffalo came in at 175 mbps.
We had left TX beam forming on throughout testing, as it is enabled by default on the AirStation. In this case, you can see how the router starts off around 150 mbps, then shoots up to 250 mbps after the beam forming learns the location of the connection.
The Buffalo AirStation in 802.11ac started out at 200 mbps; performance then increased, topping out at 380 mbps.