That's the reasonable assumption. Companies like Kind (Lush, HydroGrowLED, Blackdog, GrowBlu) aren't bashful about promoting vague stuff like "proprietary blend-a-matic spetrum" to justify their high prices. If the diodes they use were anything to brag about, you can bet they'd hype that.I'm assuming cheap generic encapsulated leds for 90% of the rebrand market, possibly "5w" multichip for higher profit margins........
Hard to believe they're suddenly humble when it concerns the diodes they use, their efficiency, etc.
I don't care what anyone uses. I'm sure Kind (et. al.) grow well. But, for prices approaching $3 per watt, I'd like to know what I'm getting (and have a lifetime warranty, planned upgrades when technology evolves, etc.). If I were going for mystery stuff, MarsHydro or Vipar(ebay) at $1 per watt looks better to me.