Unsung have been one of the better and more consistant OEM makers of standard range Epis in my experience.
Saien are pretty good too.
I don't think we should read too much into which factory a guitar came from though. There are good and less good examples from most sources.
As for the Korea versus China argument. The early Chinese production maybe suffered from the factories being at the beginning of the learning curve. In terms of fit and finish they've come on pretty well in the last couple years.
[Though QC isn't what it could be]
Again, to state that Korean production is always better than Chinese [or vice versa] is a bit daft ;^)