The PC version of this was interesting in that you could drive at the same speed as the civilian traffic for ages unmolested by the enemy cars. The bridge out sections were also missing, instead the road would suddenly become incredibly narrow forcing you into the boathouse. As arcade to PC conversions of the time went it was a pretty good version, especially in the light of the dire CGA version of Contra.
If you still want this game it's available in a fairly nice version for the Game Boy Color together with Moon Patrol... all the elements are there in tiny-graphic'd form.
Once you got a bit bored in Spy Hunter, there was always fun to be had trying to bash off the truck that deposited your new cars onto the road.