I'll give a different perspective.
IMO, lasers and other training aids have their benefits. But like most things, more than the tool, what you practice is more important. Unfortunately a lot of people 'think' they know what to practice but they don't.
So whether you shoot a thousand rounds a day or dry fire with a laser for hrs on end, if you're not practicing the correct things you're just wasting ammo/time.
That's where a good coach/instructor can help teach you how to coach yourself. Pros benefit from coaches all the time, so can you.
That's where lasers/dry firing really pay off, cause unless your backyard is your range, most folks can't go 2-4 times per week. But you can use your laser and train everyday. Assuming you're training correctly, you're handling and practicing 50-75% more, which I can almost guarantee will increase your success on the range.
As for airsoft, I've never used it. I draw my experiences from SIM training (I.e. Marking cartridges). With that IMO, there is nothing like playing out scenerios in realistic man-on-man training. It's the one part of shooting guns where you can't really 'train' by shooting at each other, so what better way than with marking cartriges or BBs. Shooting on a flat range is waaay different from someone who wants to 'kill' you too.
Lasers is geared toward marksmanship and airsoft more toward testing/improving tactics.
Bottom line is don't box yourself into a rigid training mentality. Always be flexible and always look for different methods to make you better. If you're trainig for SD, you're trainig for a very fluid and dynamic event. You're training should allow for that. From that you'll find what works best for you.