To me n this is just my thoughts (I might be completely wrong but) it doesn't seem logical that plants only use certain wavelengths, I understand that there r certain legnths that r used more then others but a plant isn't gonna be like alright that's blue oh that's red mmmmm oh what is that orange eweww no rejected...nah it's gonna take in all the light process it n use it for watever it uses it for weather it's flowering, growth, stem stregth, pest or disease contol, creating resin and so on...all I'm saying is yes mh n hps more intensity which = more penetration but again out of all the wave lengths ur only using 2 out of what 7...I would much rather get a assortment of cfl from 2700-6500 n a nice size led That's 5 or 7 band to try to emulate the actuall stages n wave lengths that the sun goes thru from dawn to dusk, n not to mention u prolly gonna save $$$ on da electric bill not as much heat n way safer...like I said I could be completely wrong n totally fuck my grow up but it makes too much sense to not try using all the wave length/light bands possible...let me ask is growing indoor better then outdoor??