Ive flown transpac on KE several times in F - their lounge at ICN is very nice - seats are very comfortable - some of the lounges have seating that focuses on form over function. In-flight, I found the service very good and the old F seats were flat but not great, although I think most US routes have now the new F pods. I do think I was the only non-Korean in F.

KE has a very good network to China with good connections and I would certainly choose them over any of the US airlines.