In theory, if I had to get out of that area, no way would I try to get away on US-1 or I-95. I'd try to get to 17 or 15, maybe cut back on 29 or 66.
If they don't get this scum, you folks in Manassas and Leesburg watch out later today. In fact, if you're in Fairfax, Montgomery or Loudoun, you'd best go fill up now... shooter can't physically make it there till about 11.
17 from Fredericksburg isn't a direct route to either 66 or 29...it involves several turns, which someone who is being chased by the police might not have the presence of mind to take.