I have to agree with renosteinke. I work for a county school board and we have plenty of each. For an inside facility where you have to read labels and just generally exist I'd take MH every time. For an outdoor facility, where the glare and color disturb the neighbors I'd take the HPS. In a nutshell ... parking lots work better in HPS but gymnasiums work better with MH.
We have the new no delay MH bulbs now also. They come to life as quickly as an incandescent when turned off & on; NO delay.
