We use Mitsubishi projectors at school. I can tell you that out of all projectors we use at school, Mitsuibishi overheat the least, are the quietest. But they also have the least vivid image. Somewhat hazed over. Like if you have had your eyes open for a few hours in a swimming pool, chlorine making a white haze over everything. But then we use the same Mitsubishi model, so it could be just that one.
Infocus are the top of projectors though.