Hey there chances are if you are buying a used wii that is already chipped then chances are a warranty is not involved on must used purchases there is no suchthing. Now what is important is what firware is this wii at if you are lucky it will be 4.0 or lower but if its 4.1 or higher you can still softmod the wii everything is on the main page. Yes you can still use dvd playback on a chipped wii through the homebrew channel as a matter of fact when you install divx one of the options is for a chipped wii. My suggestion if the chipped wii is lower in cost then go for it, and right away softmod it.