HPS can be up to mid 40s on efficiency(I think the duel ended gavitas pretty competitive and much more powerful than any LED on market.) and I highly doubt you will get 62% in a real world application unless you under drive the LEDs so much they barely push light out(which makes the price tag go up more since you will need more COB's and drivers to cover the same area as harder driven LEDs).
http://www.gavita-holland.com/index.php/products/proline/item/gavita-pro-1000-de.html
That one light is like 5 grand of LED's to cover the same area and get similar results. Please tell me why my thinking is off and please provide some facts not just your opinion because I would love to believe in LEDs again but until they can bring something to the table I just can't support wasting money like that.
your full of it ... please go away, this is NOT the HPS section of rollitup/.