Briefly, the key advantage of blasters is that although they don't do much damage in any one blast, their recovery time is very, very short. This makes them superb in real-time combat (with one major limitation), but very poor in turn-based.The other limitation of blasters in real-time combat is when you are facing a swarm of powerful opponents with ranged attacks. As each one becomes damaged, it retreats to allow others to close in, but the fact that it's damaged does not reduce the damage that its ranged attacks can do to your party. What this means is that you have to do extensive damage to the whole swarm before any of them start to drop. And while you're doing this, the whole swarm is concentrating on your party. You're unlikely to survive this without having to run and heal. Blasters come into their own when you're dealing with a single powerful monster in real-time.
A far better tactic to deal with a powerful swarm is to concentrate on one opponent at a time. You have to do that in turn-based mode, and for that, you need weapons that can do massive damage in one round, as Radek suggests.
