Get the sony. JVC is nothing to shake a stick at. Low quality stuff. Any stereo will fit in your altima because most nissans are ISO mount so that means you use the stock brackets from the stock radio and just attatch them to your new deck. Also, use the new ISO screws that come with your sony or whatever you choose. Do not use the ones from the stock radio. Try not to strip the factory screws when you are taking them out. Sometimes they are in there pretty hard. Get a big screw driver and tap them with a hammer before wrenching on them. Trust me.