$999 to be precise
The mitras has been shown many times to equal both the power and the growth of a MH, furthermore you have infinite adjustments to the spectra without having to change a bulb, (as you do of course with other full spectrum LED`s Like Radion another fine fixture)you also have the ability to properly dim the fixture with the built in (only available on Mitras) Linear dimming technology, no thats not the same as digital dimming.
Then of course there is the electrical power saving.
As for tanks under mitras
http://www.canreef.com/vbulletin/sho...wpost&t=101801
The Mitras was specifically designed to take on MH and T5 in one fixture, this is what you pay for.
But I dont want this to be Mitras Vs all of a sudden, as Aquattro said there will be fans in both camps, all i will say is if you are going to take the leap into LED then spend the money and it will pay you back, try and do it on the cheap, I do not see that it will.