1,200W rated output sounds a bit too extreme, mate. Are you planning to run 2 x Vega 64s or perhaps a mining rig with it?! For most scenarios, a 450W = 650W PSU is enough. More than enough, in fact.
In any case, I've never heard of this brand before, but that doesn't mean it's terrible. It could be quite the opposite, for all we know.
You've two options:
- Get a smaller 650-750W PSU from a reputed brand (Seasonic comes to mind).
- If you MUST have 1,200W output then check the voltages of the three rails first, before putting it to good use. If they are well within 5% tolerance then you're good. Otherwise, buy something else. And keep an eye on your PSU's temperature and periodically check it to see if it's overheating. I, for one, use my good old hand after few hours of stress testing. If PSU feels lukewarm then it's most likely good. Whereas if it feels hot to the touch then there's a good chance that it might go kaput in near future!
Hope it helps.