I replaced my stereo w/ an aftermarket unit, was in the vehicle for about 2 wks. As most Mazda5 Sport owners know, its a $700 upgrade from the stock unit. The only difference would be that you wouldn't have the steering wheel controls or the extra 2 speakers (tweeters?). Make offer.

http://images.mazdausa.com/MusaWeb/images/vehicles/gallery/MZ5/pho_gallery_MZ5_int6.jpg