Before I saw the video clip, I would never have believed that this involved such a distinctive weapon. That's not really a handgun, its more like a compact rifle and is much more difficult to conceal and deploy than a semi-auto pistol. See video at 0.24 through 0.65
If the reports are accurate that its a 10mm then its not a MAC=10 or an UZI though there are clones of both those models out there. Its not a weapon that most people would carry for personal protection...and the whole interaction does not flow like a road rage incident, there is nothing demonstrative about the gunman's demeanour and who carries both such a weapon and a mask in case they get cut off in traffic? Considering the time interval and the reported extent of destruction to the Durango: this feels planned and targeted, by someone who has had some practice.
JMO