i use the slide card method, you have to swap disks and all, but it doesnt void the warranty and you dont have to solder nothin in, no need to worry about a chip burning out ya systems and fuckin it up....
there a flip top model thats 100% better...only 39.95, that uses the same swap disk method but is just easier and sleeker
www.modchipkits.com/pages/ps2cover.htm