Actually bro, its gonna be density that inspires HPS.
Unfortunately for us CFL users, The intensity isn't enough to produce the most dense buds. My indica came out pretty dense but the sativa was very airy. I think cause of the light requirements for sativa are higher. I noticed that the indica wouldn't survive in direct sunlight while the sativa seemed to soak it up and love it.
Keep that in mind when you decide on strain. :thumbsup: