Re: Korean vs. Chinese Kantucky KM-150S
I'm going to say, likely not better than the more recent made in China. If the Chinese one is older than the Korean one, then the Korean one is likely better. IIRC, the manufacture for many brands left Korea for China and underwent pricing and construction improvements around 2001 or so. That said, these are inexpensive mandolins with some variability between each other. The particular instruments would need to be compared head to head to see if there is a marked difference.
I would suggest you will get a better upgrade by saving your pennies until you can purchase a better mandolin all together. Both of those KM150S models may have solid tops but they are most likely pressed not carved. Carving seems to be much more the standard now and gives a better result, in general, than pressing to shape. You can get carved top and back instruments from Kentucky (505) and Eastman (305) for $500 and $400 respectively for example, on a reasonably tight budget.
There are two things to aim at in life: first, to get what you want; and, after that, to enjoy it. Only the wisest of mankind achieve the second. Logan Pearsall Smith, 1865 - 1946
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