Japan and Korea in one trip? Rough data maths from Silent eSIM's rates today (3 Nov): Japan from $2.76/GB, South Korea and Hong Kong from $1.64, Taiwan from $2.20.
At around 0.5 GB a day for maps, translation and messaging, ten days in Japan is about 5 GB (~$14) and four days in Seoul about 2 GB (~$3.30). So the Japan leg is most of the bill, not Korea.
Korea tip: Google Maps can't do proper walking or driving directions there, so get Naver Map or KakaoMap before you land, which pulls a bit more data in the first days.
Whatever's left over doesn't expire. Prices per country:
#travel #esim

Silent eSIM
Rates by country — Silent eSIM
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