As lasers get cheaper, people will put more and more higher powered lasers into smaller spaces. I was writing up my safety record for a spring festival last night and surprised and perturbed to find I was going to have to turn my 800mW greens down to under 100 to hit MPE. Although I would love to justify buying more and bigger lasers, I've realised that my 1-4W range of projectors will cover 95% of the jobs I do.