I bought a used X3 from someone. I understand that the X3 is only for custom tunes? When I picked it up, he said to hook it up to make sure it worked before I paid him for it. I told him that I didnt think it would have any tunes on it, so it shouldnt work. Well, we pluged it in and downloaded the extreme street tune. I went for a ride, IT WORKS!! Its great! My question is, is it supposed to work this way? No custome tunes needed to purchase? No strategy needed? I just wanna make sure its safe. I think it has: extreme street, smoke, and extreme smoke. Then it has the factory tunes: agressive tow, 50hp tow, 65hp tow, street.....Just not sure whats going on with it.