Great game, really enjoyed the strategic planning of it. In regard to 25352's comment. The +10 (or whatever) indicates it does an extra effect on top of damage whenever it hits. For example that flame thrower would do between 8-14 damage but would also add 10 heat to the damaged mech.
Overloading your enemy with heat is a very viable tactic and one my mech 'Axios' loves to do with dual flamers.