I use them. They are nice to me. I can't compare them to PC as I have never seen the pCs btu I have 2 24" Over driven over a 15 gallon and I get plenty of nice growth. The only thing that is not great in my tank is the Glosso but its a little lowlight for the Glosso to stay low. It wants to grow up more than usual. Good ferts are most important for good growth though. As far as color goes, they do make the red plants not only look redder but they do grow a little redder also. Don't know why, must have something to do with the spectrum causing more of the carotinids (red pigment in chlorophil, sorry if I spelled it wrong) to be produced. To the eye though the tanks looks a little to "pink" and I recommend supalaimenting it with a 6,700K or something to even out the color. They are nice bulbs fopr growth though and the price is excellent.