I hear Amped Wireless is coming out with the R10000G witch I believe is your same router only with Gigabit ports.
So, overall do you find that the RT-N66u is the better performing router? I see mixed results from your tests.
Yes, I noticed Amped is releasing the gigabit version next week.
Given the addition of gigabit ports, IPv6, 5GHz, USB ports (in case I ever need them), faster CPU and higher amount of RAM ensuring it can handle loads and multiple connnections with ease (if needed), easier firewall settings (although the Amped did pass GRC Shields Up) and apparent amazing build quality of the RT-N66U, along with the fact that it may have fixed my Netflix issue,
the RT-N66U was an easy choice over the Amped for my needs and desires.
From a pure wifi performance standpoint, the results of the RT-N66U exceeded my expectations (especially given the transmit power setting concerns I had and how great the Amped R10000 wifi performance already was compared to the E4200). They were indeed somewhat mixed when compared to the Amped.
That being said, they were close most of the time and the RT-N66U performance was great - signal strength was great throughout the house and throughput was decent enough.
The biggest good thing about the RT-N66U: My Blu-Ray player in the far opposite corner of the house one floor down is getting a 5 bar wifi signal (out of 5) from the RT-N66U which impressed me. I suspect their AI Beam Forming helped it beat the Amped in this particular test (with my laptop tests in the same room, but not tucked away in a corner like the Blu-Ray player, the Amped was better)... So overall I prefer the RT-N66U wifi (can only compare 2.4 GHz) since it seems to provide slightly better/ stronger 'directed' coverage in the furthest locations of my home than the already-amazing Amped which blasts the signal all around. 5GHz was also impressive (only tested signal strength) on the RT-N66U compared to my E4200 (the Amped is single band so I can't compare it to the other two routers.
The biggest surprise in a not so good way was the lower throughput in the adjacent bedroom when using the RT-N66U as opposed to the Amped. I did test them a day apart though so who knows if something else was playing a role (however, I did confirm my internet speed both days first, left the laptop and any running apps in the same state and put the laptop and adapter in the same exact spots in each of the three test locations).
I suppose for cases where budget is a factor, the Amped R10000 may fit many users' needs. The caveats being IPv6 may not ever be supported by it (not sure what their plans are) and that weird Netflix covers issue may indicate an obscure issue (I would need to confirm it by trying Amped again - maybe it just needed a reboot or something).
Mfr. Refurbished E4200 v1's for only $99.xx shipped with mfr warranty may also work for many users' needs.