I used to work in the Port and we had the Kia's and Hyundai's coming in off the boat my job was installing accessories, decals, emblems the cars seem fairly well built and we moved a lot of them through 3-400 a day easy. We worked on numbers we generally were expected to move around 500 cars a day with a 24hr shift.

The biggest things I noticed:

Paint- not great if you have ever worked around paint take a close look and most are really badly orange peeled. I remember some guys in the body shop area that hated mounting spoilers because they always had to buff them out from scratches and when they did that it made the rest of the cars paint look even worse.

trim- mud flaps, fender well etc screws are not that great lots of just plastic snaps that come apart and screws a lot of time are stripped.

interior trim- most of them are fairly decent for the price range everything being just plastic.

I am sure I could come up with more but ya. They are what they are cheap economy cars. I personally wouldn't buy one but from how many we had to work on they obviously are pretty popular.