I haven't ran a speed test with the phone itself (the accuracy of apps like speedtest.net are often maligned), but have noticed the device-to-router rates which the N4 and N7 on 4.2 report vary much more than I saw with my GNex and N7 on 4.1. When I first connect to my 5.0 ghz WiFi, the N4 will show very low Mbps rates, like 6 Mbps, but will eventually top out at 72 Mbps. The GNex almost always reported 65 mbps, its top end rate, unless I was nearly out of range of my router. My router supports 450 mbps on 5 GHz. I know the N4 has a better WiFi chip than the GNex. I'm thinking it's a bit more sensitive to interference though.