NorCal - you need to look at the "footprint" you want to light and the kind of grow you will be doing. Check out this thread - this guy has 4 x 1000watts, but claims to get around 12 pounds per harvest... and he's doing a 4' x 8' sog.

Decide exactly what and how you want to grow and it will then make your lighting decision much clearer.

PCimp: