For example, I saw some people saying that there is no difference between Mars II and BlackDogLED. I don't understand anything anymore lol.
Blackdog, Blackstar, HydroGrowLED, GrowBlu are rebranded Chinese imports sold with mystery spectrum hype for a premium. If you were going to buy those, just get TopLED/MarsHydro without the middleman.
I've watched Mars grow journals and I'm not as pessimistic about Mars as others here. There's not a lot of money put at risk, and the company has a public support forum at 420mag which makes it much less risky than dealing with an anonymous eBay seller in private email. Just look at the grow journals and make your own decision. There's a guy doing one right now in the
newbie forum. (<<link).
Another Chinese light which is suggested as a last-resort is VIPAR (on ebay).
With either light I think you'll want to step up to something more efficient. But, I could see using a cheap import for a couple grows to get started. They'd serve as backup fixtures, a fallback when a fixture fails.
I don't know if I'd buy as deeply into it as you've communicated. If my goal were to cash-crop, starting with inexpensive lights to generate some revenue to afford more expensive ones, I'd probably start smaller.
Check out the 420mag support forum. You'll find photos of grows there too.