the only games, from PC, i've played online via both DSL and Dial up are Diablo II, Nexus Kingdom of the Winds and Dark Ages. And I can only tell you from my own experience is that there was no difference between Dial up and DSL for Diablo II, which was running the cd most of the time, but with Nexus and Darkages, which did not have the luxary of running on CD and just had 50mb of some files on the HD, that between Dial and DSL, there was a HUGE difference with every aspect of the games, from the speed of walking around, to the battles that involved 100+ players at the same time, as with just regular hunting. FFXI i imagine would be like Diablo II, probably has 20GB of info on the harddrive for fast access as well as the CD. But i'm just guessing at that.