400w cmh or 1000w mh/hps?

Very simple question. I have been doing a lot of research lately on which light setup I will be upgrading to. For cost efficiency/productivity purposes I have decided HID is the direction I will be going for now. The question is do I go with 400w CMH's or 1000w MH/HPS's? Obviously I would need twice the amount of 400w setups for coverage purposes, but I am ONLY concerned with what is best for my plants.

The grow environment will be deep water culture (5 gal's), proper exhaust and air circulation is in place (cooling will not be a problem), the grow area is surrounded by mylar. It will be a SCRoG style grow using Advanced nutrients sensi line of nutrients. Any more details you would like to know don't hesitate to ask, I need as much input as possible before I make my decision.

I am going to be purchasing at least 2-4 new lighting setups (depending on which wattage I go with) within the next 7 days, so I would appreciate any high-quality input you might have to offer. Thank you for your time.

bump

1000w more light intensity and light penetration 400s make shit soft bud, failing that 2 600s, but swerve 400s unless your concerned about energy/heat.

The new dual arc 1000 bulbs rock for light spectrum like the cmh maybe one of the factors you may want to consider is you can get good uvb output from the cmh!
I think a 600 hps and a 400 hps with a cmh bulb in it would be a great mix with more total light output than a single 1000 watt dual arc!

What do you care about most I guess light output usability and uvb?
here is how I would break it down!
Best usable light for a plant also uvb = cmh down fall is light penetration
1000 hps deeper penetration than a 400 but all color is in red orange!
1000 dual arc bulb for hps sacrifice some total output for better color and plant usability!
600 hps best output per watt of any bulb just a little less penetration than the 1000 watter but almost half the power!
Still most of the color in the red orange!

So if you are looking to have a 1000 watts I think the best mix is the 600 super hps mixed with a 400 watt cmh great output from the 2 bulbs both in color and total output and the bonus is the uvb from the cmh!

Nice, good input thanks guys, starting to lean toward the 1000. I have UV-b bulbs already so that negates a lot of the benefit you listed. I'm thinking in the interest of cost efficiency (dollar per watt, dollar per sqft of coverage, etc...) and penetration the 1000 is for me. Any more input is greatly appreciated, though!!

If you want one light that does everything the 1000 watt hps is for you if you want the most light in a balanced spectrum the hps cmh combo cannot be beat!

One point I think you are missing is light penetration of the 1000 is best but it is all in one color witch the plant will not use as efficently!