Luckily for all sci-fi space people lasers are the big suck for any sort of planetside deployment, and can be countered relatively easily by things that refract the beam. Unless those things can be overcome, I would suspect they would remain a specialist type of weaponry. You'd mount them on spaceships, because the whole speed of light thing is pretty handy when you're engaging at distances where light lag becomes a thing, and there's nothing in space to refract the beam over those distances. Much, anyway. But their characteristics really don't lend themselves to personal use. The instant hit factor is nice, but it's something that becomes more of a benefit at longer ranges. So they might be more suited for space use, but a lot of combat between people in space is going to take place onboard of space ships. That is, in extremely close range. There's really no reason to use a laser in those situations.
So I'd expect some sniper type applications, but not widespread use as a standard weapon system.
I recall some official material stating that a lasgun has about the same stopping power as a .50 BMG.