Hello all, long time reader, new forum member. I have to agree with irev210 the r8500 has been rock solid. Like a lot of folks, we seem to have been taken unawares by the explosion of network devices and implements of horror (the latest being a refrigerator with internet diagnostics, promptly blocked since it likes to hog bandwidth). In short the tri-band has helped with bandwidth congestion. Christmas was the big test. We have 7 adult children between us, with a few significant others thrown in, each with smart phones, tablets and laptops, so our house is an internet café on holidays. I did not set up guest networks since our children have been net security conscious for a long time. I did divide all mobile devices, excluding laptops to one 5 GHz band, and laptops and desktops to the other 5 GHz band (SSIDs appropriately named "Mobile" and "Desktop"). The 2.4 GHz is set for Direct TV Genie/Media Server, and other legacy devices like printers.The r8500 took it all like a champ, even a few sessions of FaceTime.
I am a gearhead, and my interest lies mostly with pc hardware. I know enough networking to be dangerous to myself and others, so I rely on real world results. What I can see and use, is my benchmark. I replaced an ASUS RT-AC 68P(U) so that is my latest basis for comparison. I live in a tri-level house, with the router being on the middle level (ground), and users mainly in the home theatre (lowest, basement level) and upper levels including the bedrooms (technically 4th level since basements aren't usually counted). With the ASUS I had to resort to running range extenders and old routers configured as access points. Those are now no longer necessary.
I read the SNB review on the r8500 several times, and while Greek to me in most parts, I did comprehend there should be no appreciable increase in range. My experience has been contrary. Taking a conservative WASG (Wild A** Scientific Guess) I am seeing about a 25% increase in range. This would be a diagonal upward distance (think 7 o'clock to 2 o'clock) of about 90ish feet through 2 flights of stairs, 4 walls and assorted ductwork, wiring and plumbing. It is sitting in a not ideal location on a glass shelf under a LCD TV next to a Blu Ray player, surrounded by the cable modem DTV receiver and DTV cable modem.
I am a gamer, so the capstone for the above mentioned test parameters was a 40 man world boss raid in World of Warcraft with maxed out settings on video (SLI GTX 980 cards), so there was a lot of data being pushed in both directions, compression and all. WoW has a built in meter for signal delay (lag) measured in milliseconds. Additionally it is color coded to monitor at a glance (Green, Yellow, Red). At the peak I was seeing 12 to 14 ms lag, with a frame rate of 96fps on IPV6. IPV4 yielded similar results at 22 to 24 ms lag with 82 fps. For reference, it is considered good to be under 300ms lag at an average fps of 60ish. I am on Time Warner Road Runner cable, with their 50MBps plan. I am on a neighborhood loop that has at least 5 homes attached, but Ookla gives me ping ratings to my Chicago game server relay of 62 to 66MBps on average.
This was with stock out of the box router settings with no QoS or metering, with the latest Netgear firmware, with simultaneous access of mobile devices and Pay For View streaming on the 2.4GHz band. My gaming PC is connected via lan 1 (no switch, not aggregated) and the 5GHz-1 band. There are currently no NAS/USB devices attached.
It is expensive, but appears to be the solution I needed. I did manage to get a pre Christmas sale price of $350 at the local Best Buy (price matched with New Egg and Amazon). Hope this sheds some perspective on the discussions. It may not be the solution for everyone, but it delivers for me currently. Time will tell.