Mixed reviews out there. There are some good videos out there on Youtube doing long term reviews and test on such parts which are worth trawling through as the quality on such parts by cheaper brands does vary.
I bought a Giant TCR with NESS or KNESS carbon one piece bars. I bought a set of alloy aero bars to swap them straight over but, I was sceptical but so far, they have been working well enough to not warrant me swapping them.
What I do do notice between them and a set of Easton Carbon bars I fitted to my Giant Propel is that the Easton's don't seem to flex, they are pretty damn stiff. The Kness, or what ever bars, whilst not bad, do have a bit of flex in them under such load. Neither have snapped....
Also IIRC the internal cable routing is not as well thought out and/or finished smooth on cheap bars like it is on more expensive ones.