Worked great for me.
I just got Comcast Ultra and was using a Linksys WRT54GS 2.0 router, but my download speeds were capped at about 24mbits because of the CPU horsepower in that Linksys model.
Since the DIR-825 has a faster CPU I tried it out with stock 2.02NA firmware and was capped at about 10mbits, which annoyed me a lot since technically it should handle the full speed of my connection.
Once I loaded DD-WRT on the DIR-825 I was able to get the full 35mbit download speed of my new connection!
You can find more info/feedback on DD-WRT running on the DIR-825 here:http://forums.dlink.com/index.php?topic=9920.0http://www.dd-wrt.com/phpBB2/viewtopic.php?t=63986http://www.dd-wrt.com/phpBB2/viewtopic.php?t=57708