I played on comcast a few times once those came up.
I heard people complaining the first few days about lag, and I did see a bit of people ice skating...ya know where they look like they're sliding across the ground rather than moving their legs and walking? Not much mind you, but once or twice.
I didn't really have any complaints about them other than some of the nimrods on them being total whiners or dipshits, but you get that no matter where you go.
On trinity mojo dojo, I dad some d*****s TK me 3 times in like 1 minute, and I was the teams commander, it lost us the game it was so close. His excuse was the game was almost over so he was just messing around.....