The main difference is wattage and coverage, The coverage of TS600 is 1.5'x1.5, TS1000 is 2'x2'. and the wattage of TS600 is 100w, TS1000 is 150w. and TS1000 can be dimmed, but TS600 is no driver design.Currently in the market for a veg light for my mother plants. Noticed the TS 600, which I think might be perfect for what I need. Anyone have experience with this light? I'm assuming it's just a slightly less powerful version of the 1000.