I used both this mobile. W580i mobile is my new mobile which I bought. Before that I used W700i. Both the mobiles are very much efficient and great to use. Few differences between these two mobiles are as follows. W700i is a bar type mobile where as W580i is a slide type mobile. Both these mobile has a camera resolution of 2megapixels and they are walkman series mobile. In W580i lighting effects were available whereas it is not available in W700i model. There are five colors of mobile are available in W580i model whereas in W700i 2 colors are available.