As good as anything out there. They make a 1200 watt driver in constant current versions and meanwell does not. Horticulture lighting Group is building many of their fixtures now with inventronics over meanwell. Some of the inventronics models have slightly higher efficiency range compared to the same output meanwells but they are pretty much comparable.
I have a thread on them in the lighting section with some good links on where to purchase. It's called "Alternative to meanwell drivers" I think. Haven't seen it for a while.
Alternative to Meanwell top quality led drivers....Inventronics. This futureelectronics place seems to have their entire line of selection. One thing I noticed is you have to really sort through if the driver is 120volt capable and dimmable vs meanwell's models which are more simple and universal. EFD-1K2S420DT in Box by Inventronics | LED Driver Modules | Future Electronics HLG's elite 360 and 550 fixtures are now built with Inventronics and not meanwell. Started about 6-7 months ago. They must get a better bulk deal from them over meanwell or something.