Cost is a factor, and a significant factor, but not the only one.

Flip-side of cost is effectiveness, and it would be interesting to see real-world data on the accuracy, reliability, and longevity of Korean weapons systems in active combat. I suspect the Koreans are also anxious to see this given their own geopolitical situation and northern neighbour. The article doesn't go here either.

It does, correctly IMO, focus on the reliability of the US as arms supplier, given the increasing control over access as a political weapon of retribution and reward, potential "kill switches" in US arms, the limited total production capacity of the US, and particularly in light of the latter, stocks depletion and unavailability on the basis of capricious gallivanting into ill-conceived conflicts with little gain if not actually worsening its subsequent position, strength, and status.

The Koreas both have an extensive reliance on artillery. Seoul is within range of PRK batteries, Pyonyang not so much from ROK, but any invading forces would be. I suspect ROK counterartillery systems are well developed, and that given the effectiveness of drones in recent years and the likelihood PRK might rely on these that there are, or soon will be, effective countermeasures against them.

Antiballistic missile systems would also be useful for ROK. I know nothing of this, but find that there is a Wikipedia article on the topic: <https://en.wikipedia.org/wiki/Korean_Air_and_Missile_Defense>.

>Cost is a factor, and a significant factor, but not the only one.

The REAL significant factor is that Korean arms companies are not just sealing weapons, but also willing to sell IP to their allies for you to manufacture their weapons domestically, something very rare in the arms business.

It's why Poland chose to license and manufacture Korean weapons domestically rather than buy superior weapon systems from their EU and NATO allies and neighbors France and Germany, since those two typically only sell weapons but never IP, as they see IP as valuable trade secrets and leverage.

Sovereign supply chain and manufacturing for arms is more important for your national security than price and having the most bleeding edge systems if those imported systems can be withheld against you if your ally wants to squeeze something out of you at some point in the future over petty political squabbles, and Poland has less chances of having beef with Korea on the other side of the planet than with neighboring France and Germany. So it's the most sane decision politically. A lot of countries got bit by this dependence that it's a valuable lesson every country should heethe.