Recon units are the least powerful vehicles in the Advance Wars series.
Their main purpose is to clear up the "Fog of War" in some of the missions, and if necessary they can also take on Infantry (attacking Mech units is unadvisable, though...)
And of course, you can use them to attack unarmed units like APCs. As long as there are no other enemy units nearby, that is...
Have fun building!
