I feel like I need to address something that I have seen NO ONE mention, but I DID skip a few pages out of the 14 so far...
MANY people seem to be having SLOW router speed but great direct connect speeds and NO ONE is talking about your WIRELESS SECURITY SETTINGS!!!
I KNOW most recent COX installations of high speed systems are leaving out the SECURITY... IF you are using the usually DEFAULT WPA and/or TKIP you are LIMITING yourself to 54mbits!! They DO NOT support high speeds!!
You MUST use WPA2 and AES or you will NEVER get good Wireless speeds. Routers default to WPA and "BOTH" AES and TKIP for compatibility, but VERY few devices need it these days. AND if they DO need the slower security, you can usually set up a GUEST network with the cheesy old security for those and keep the speed settings for anything else.
While I don't have 100+ speed at my home, I DO have 50mbit speed and usually get 55 to 65 at home with boosts on big downloads to over 80mbits! And I get the wireless speeds up there. (Waiting patiently for Gigabit to come here!!)
I do have a great ASUS N900 Dark knight router (RT-N66U), and have up to about 400Mbits between computers on my network. I DO KNOW that many friends and people who come to me for computer and networking help have been set up by both COX here AND AT&T with OLD security settings and they are limited by it. (Of course AT&T here only offers 18mbits and calls it "high speed") Still, My doctor's office even uses WPA and they cant get their networking people to get them up to speed. They complain about slow speeds in their office. SAME THING!
IT IS A COMMON PROBLEM!!
If you buy a Gigabit AC router, DO NOT USE WPA or TKIP or you are wasting your time.
......Just trying to cover some important bases here.