I spent several years in Houston, and the drivers there are polite to a fault (four way stops are hilarious in Houston). But, if you aren't driving at least 10 MPH, 20+ on highways and toll roads, over the speed limit, you're gonna have a bad time. Houston traffic is the most insistently/dangerously fast traffic I've experienced.

There have also been more shootings on the road in Houston than anywhere else I've lived. So, yeah, that seems scary, but it's not something I worried about when I lived there. In the instances where someone got shot that I know of, the person was kinda asking for it (they initiated violence and the person they were beating on happened to have a gun under the seat or in the glove box).