I'm just about to make my light purchase, and it's between the 8 bulb T5 or a single 600 watt dimmable HPS for my 13 square foot (5'w x 2.6'x 6'6''h) grow tent. Which one should I get, and if your opinion is the HPS, would a 1000 watt HPS be overkill for this size area? I weighing cost of...