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Planning to stay in South Korea for two weeks. Would be nice to have GSM prepay card for data transfer.

Found two providers:

EG sim
Cost 5GB = 60000 KRW

Cost unlimited data 10 days - 38,500 won 

Which one has better coverage and more reliable. What are hidden costs? Where to buy?

There are more providers?

marked as duplicate by Burhan Khalid, JoErNanO Mar 27 '17 at 8:32

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