Watts are watts
315 cmh = 315 watts
1000hps = 1000 watts
But a better more usable light spectrum comes in play as added uva-uvb when using cmh bulbs. Philips bulbs beat out all other bulbs as far as par in a study I posted the link.
Ushio beats all in uva-ub. Once again, see link i posted.
I kill it with cmh. I now run 1260w of cmh vs 1800w hps in my flower room. My yields are the same if not better. The quality is 20% better, as far as trichs and colors. And I save on my power bill as well due to saving 540w of power usage, and my a.c. not needing to run as much.
I also swapped out 3x600mh for 3x 315cmh. I only run 1 or 2 hoods vs all 3. Growth is FAR quicker with cmh, better growth, and added uva-ub.