Just switched from DD-WRT to Tomato because I was having trouble getting three xbox 360s to work on my network.
I had tried everything and gave up.
So I switched to Tomato, and turned UPnP on.
All of my xbox's had open NATs :)
I thought everything was working perfectly but then I started to get lagged out of games (I tried about 10).
I don't know what the problem is.
I'd done ping tests using pingtest.net while the xboxes weren't connected to the network.
I get 15-16ms ping, 0 packet lose, and 0-2 jitter.
When the xboxs are turned on, sometimes the ping spikes, sometimes it doesn't.
It always spikes when I stream videos from my desktop using tversity.
Even Standard def videos!