For a micro space it's a waste of money when you consider if your 1 150w bulbs goes out you have to buy a new one and your garden suffers from a fucked up light cycle.d
You're arguing something that is a hypothetical.
I've completed 6 grows and not once has a 150 HPS bulb died. I've switched it out once, but not because it was dead.
On the other hand, I've had about 10 fucking CFL's die during those 6 grows. I am speaking from reality and experience, not a hypothetical "what if" situation.