Cars tend to be either in front of you or behind you, especially in the Death Races we have played.  If I am ahead of the pack I often find that I have no way to combat the threat from behind with most of the cars I have built so far.  

This time a rear facing gun (light cannon) should put off the opposition from lining shots up on my rear.

That said, if I am not in the lead with this car I will not have many options with just this load out…  After a few test games he may get an upgrade (and a forward facing weapon).

Not a bad garage of cars so far…