When I first created this site in 2012, I tried to include what appeared to be the biggest companies that were getting talked about the most. Of the 11 companies initially reviewed in 2012, 6 are completely dead (or un-dead), one appears to be failing rapidly, and one of the failed company's owners has started a company under a new name.
In 2012, 357 Magnum appeared to be one of the biggest, most-successful LED grow light companies. Apparently the company was sold in 2014, and they put out a single new light which I compared on this site in late 2014. In early 2015 the website was occasionally being redirected to one selling hair care products; then they let their SSL security certificate expire so you can't even purchase a light from their website anymore.
GrowBlu is dead. From what I can tell, they started in 2012, became fairly popular in 2014 and I included them in the early 2015 review. By mid-2015 they eliminated their warranty and return policy before finally removing their website. Unfortunately all their customers are now left without any warranty support.
Stealth Grow was arguably the 800-pound gorilla on the block, or at least they really tried to present themselves that way in 2012. They stopped honoring warranty issues in 2013 and their website disappeared shortly thereafter. Apparently, you can still buy some of their lights through 3rd-party sellers, but since you'd never get warranty support that seems like a really bad idea. One of the original owners has now started a new LED grow light company.
Grow Stealth LED seems to have vanished without a trace after my initial 2012 review; I don't know exactly, but they seem to have gone out of business sometime in 2103.
Sunshine Systems' website is now being redirected somewhere else; I don't know exactly when they disappeared either, but late 2013-early 2014 is likely. In 2012, they were making ridiculous claims about how a couple hundred watts of LEDs could replace a 1000W HID. Clearly this tactic didn't work out for them, but many other companies still haven't learned the lesson that they can't lie and still keep their customers happy for long.
As of November 2015, Grow LED Hydro's website still exists but is largely broken. They promise an update soon with their new 2011 models, and their website is frozen as it was in 2010. I didn't include any of their their lights in the comparison, but I have to wonder why someone is still paying to keep this website online.
At Death's Door?
Hydro Grow appears to be failing as a company in the same way 357 Magnum and GrowBlu just failed. In February 2015 they announced a March 2015 Kickstarter campaign to fund development of a new light series, available in August 2015. In itself it isn't a great sign that they have to ask for money to develop a new light– but then March came and went and still no Kickstarter campaign, and now August has come and gone with no campaign or new light. If they were really an active company, you'd think they would at least update their website every few months and remove outdated promises! Their X-Pro series of lights was made special-order only in August, recently re-worded to Up to 2 Week Lead Time on Shipping— so they aren't even maintaining an inventory of lights. I suspect the company will be dead within months. Could this be another example of the apparent COB curse?
Spectrum King LED is owned by Rami Vardi, one of the former owners of and spokespersons for Stealth Grow LED. The Spectrum King intensity comparisons on their website and YouTube videos showing a grow-off between various HPS and LED lights appear to feature an old Stealth Grow SG 602 light as "the competitors' red and blue LED". This somewhat ironic choice does make sense if you want to find an ancient, old-technology LED grow light to make it look like it doesn't stack up…