NBA Live 2004 is, IMHO, incredibly improved over 2003. I'm sure you will hear the same from most people. Everything is just so much... better, the gameplay is much more realistic. They have improved the sounds I think (except it still whooshes when you dunk), graphics are improved (especially now with the headshape editor

) and gameplay is incredibly better. It even runs a whole lot better than 03, allowing way more fps. Go for it, I say!