The only problem I see with demo charges is that they seem pretty hit-or-miss. They actually have a much larger explosion radius than you'd expect and they deal so much damage than anything that is actually hit by it dies. This is ok, after all it has a long timer that allows for retreating everything but weapon crews or grenaded vehicles.
However, everything within 2.5 units is dust by default whereas everything up to 5 units radius has a ~60% chance of dying (0.25*340 is still a lot). This ring of randomness makes them a bit too unpredictable and complicates judgement about which units to move/retreat.
But most of the other grenades also have this problem. I'd really like it if all those AoE attacks became less random.
