These great weapons can wipe out loaded trucks, tanks and exposed HQ's at long ranges using Opfire or direct fire.
Here are some tips from my experience to stimulate comments
ALLIES. Once they are spotted you must look at the visibilty of every hex you plan to move through and try to sneak past using Wadis or Forests
You will have to take them out by Air Attack (unreliable) or sacrificing some light fast tanks as the guns only get 2 shots /turn
AXIS. Place for maximum visibility and decide whether you want to use Opfire or not - turn by turn. When the enemy tanks get close decide whether to fight it out to the last or flee to another spot with good visibility
I have assembled 7 files (with comments) for those who wish to practice.
of these are in Matrix JTCS the other in my personal collection of TS scenarios.