Jef79answered grow question 4 years ago Hello.. Hope you are well.. I use both.. In 1 tent i use sf600x2 and in my other i use sp150x2.. Personally i prefer the mars brand.. Apparently the efficiency is a bit better on the sf's but i have noticed they produce more heat as they dont have a cooling rack like the sp.. Also the sp150 are very well built lights,u cant go wrong with 2 or 3 of these bad boys in a small grow space.. Stay safe n gud luck with ur gardening activities.. 👍🍀