Hello all. i am stuck looking for the most efficient 600 watt HPS Bulb on the market. It is difficult to find spectrum ratings, and PAR ratings for some of the most popular bulbs. Many online stores wont even have the Lumen rating. I know prefixes such as Super or Enhanced usually refer to an increased amount of blue in the spectrum; but where is the line between average and extra? Seems to me all HPS bulbs are between 85K-95K lumen. From what I've seen, Hortilux looks like a favorite, and while they nailed it with their 400 and 1000 watt lamps, the 600 is lacking at 85K-88K (depending on who you ask). Grolux @ 90K, Agrosun @ 90K. I am using a Lumatek digital ballast. While I'm at it, where is the most efficient 600 watt MH bulb?