I have two lights for my 4 X 4
1 is a 315 CMH which i will try in the fall
1 is a 550 watt mcob light and that one did work very well on my last grow. Everything finished before it should and the harvest was good for a newb.
For other newbs I am looking for good cost altneratives to the cob. MARS are cheaper but cobs work better. Both require no heat dissipation over the HPS.