Evaporation is still an issue. I have approximately the same amount of evaporation than i did when i used T5 lighting. So my advice is to still be prepared for evaporation in any reef tank when using LED,s
This has made me make allowance for this with my DIY hood project. I was going to enclose the top, but think the best way to go is open top.
But at least im saving 50% on my reef lighting bills.