The game is stable for the most part on the 360, and unless there's a lot of things going on in a small area (Besieged, Campaign, most auction houses), you won't run into any horrible lag. Graphics are good on an HD display, though you could do much better with upscale PC hardware (though such is pricey). The biggest caveats to playing on the 360 are having to use another machine to look up information (I solved this by setting up my PC and 360 right next to each other, each with their own monitor) and having to sign in to Xbox Live in order to access PlayOnline (you can play FFXI while singed out of Xbox Live, but you will get boot the boot if you try to get on PlayOnline and can't sign in to Live).