LungsOfGlory, I don't have any experience with Mars Hydro -LEDs so I cannot say if they are any good but I do have some with GN's MS0006 and their brand new model, HS1. Just check some of the growdiaries with HS1 people are doing here. TaNg is right now getting over 2 gpw with his grow up with two of those units.
Sure, they are expensive but believe me, after I settled for couple of 100e units and realized they barely grow nothing but nice lettuce I had to cave in and first get the MS0006 unit that worked wonderfully and now the new HS1. HS1 draws only 75w on average that produces amazing good results. Just remember that you cannot bluntly compare wattage of an unit to the yield they might produce, but it is still an usefull indicator how well the light is performing. It is like comparing wattage of an amplifier in estimating how many dBs a speaker will burst out. Just check any modern studio speakers, like Genelec, they take so little wattage but the sound is full and wide. Same thing with the latest LEDs.
Yeah, I admit, I have become sort of a GN -fanboy. I am so impressed with their quality.