Oh man. I really can't understand you. Why you ask such questions? These games has nothing in common (except cars). You better ask Call of Duty 4 or new Medal of Honor (can't remember full name) or similiar stuff.
why do people keep trying to compare completely different things? it's all a matter of preference. if you like racing more, then you'd like burnout. if you like doing missions and killing people, then it would be gta.