I've read this question, and checked out the supported devices list, but am looking specifically for a gigabit 802.11n router that is easy to find and fully supported by DD-WRT.
It seems like some of the Linksys WRT300N-series are a good idea, but I'm not sure which of these are easily available and fully supported.
If you think 802.11n is a waste of time, that's also an acceptable answer. Just let me know why. In that case, I'm perfectly happy to go with the standard Linksys WRT54GL.