Japan, because it is the least worst of the three.
S.Korea if not for N.Korea
so I 'll go with Akihabara
Japan because I am currently living in Japan. Also China? Not a great place to live. South Korea has it's good points, but too small, too close to North Korea, and it kind of smells bad(at least it did last time I went there).
Taiwan (Kinda China depends on who you ask)
Really cheap stuff, awesome stuff, cheap travel to Japan and the main land. Plus i've been and I loved it.