I get lag sometimes, but I assume this to be interference from objects in the house, other wireless interference, and the general connection lag between playing someone who lives away from me a bit. The lag that I get, however, makes it slow for a little bit, but then regular speed picks up. I also have the option of borrowing a friend's ethernet adapter, so this could make my connection even better.
Setting up a specific connection profile like I suggest though makes it so the router does not auto-assign your wireless connection each time and instead sets up something it will always go to. Also, doing this makes it so the chance of the match cutting out is low, although it happened to me once; I have only tested my connection against someone on my friend's list once, and the second time got interrupted and disconnected but I think that is a rare thing to happen.
Meh, I don't really know. Setting up the connection couldn't hurt though.