idk man, i dont like to drive high, it just seems like a way asking to be caught. I do do it occasionally when im out in the country (kinda were i live). Driving in a city would suck tho, too many oppertunities to fuck up. Like 40oz was saying, judging traffic is difficult: making a left hand turn. You gotta pay attention to stop lights. I guess i'd just recomend 'practicing' it somewhere that doesnt have a lot of traffic, if any at all.