I've had great success for over 2 years now using two Theroreme Innovation's ProBloom 600 LED grow lights. Abt six months ago we purchased 2 more. Currently each pair covers a 4'x4' tray usnig a light rail. Production is equal to or slightly greater with the TI's vs. 1000w HPS over each tray. The trays that had HPS are now using PSMH 1000w 3k bulbs for flower and 10k bulbs for last 2 weeks. Again comparable results, maybe trichomes amber quicker under the PSMH, but not my much.

My homebuilt T5/LED hybred, that I've been using almost 4 years now beats the crap outta 1000w HPS, but I do use a bunch of differant supplemental lights with it.

Yup, LED's don't work.