Despite the claims that the bestva 1200 replaces an 800w hps, it doesn't, its a 240w light and for good results would probably be best suited over 2x2.5ft , you want to look for the wattage draw and assume it takes about 50w per square foot to get solid buds. (with cheap LEDs)
Taking that into account you would probably want 4 of those lights to properly light a 4x4 tent in flower or two of them to veg well.
So the cheap light no longer seems so cheap.
We aim for around 30-35w per square foot with higher efficiency LEDs like some of those suggested above, they cost more money.