Guys just a bit of an update. Sold my XBOX 360, I boroughed my friends until the XBOX1 arrives in Nov. When I configured the DGL-5500 2 weeks ago, I proactively used the port forwarding rules Furry had stickied that covers it ALL.
The port forwarding rules that work for the 4500 also works for the 5500. After I configured the Xbox wireless on the 2.4ghz, ran a XBOX live test, everything was a green check mark. I logged back into my profile and played GOW judgement had OPEN NAT..no issues and ran great.
BTW ....friend has the older XBOX, with the external wireless covers both the 2.4 & 5ghz bandwidth, although initially I had 1 bar on the 5ghz, I updated the xbox on that freq. and when it rebooted, there were more updates and it lost the signal all together. So I ended up using the 2.4 for gaming. Have to admit the 5ghz amp is weak, I was really hoping for a much better signal. My DIR865-L reached in those areas and was great!!!