MSCI Korea: 10Yr returns: 13.09, P/E=15.88, P/B=2.26 Semiconductors=19.78% of Index
MSCI Taiwan: 10Yr returns: -1.58, P/E=20.17,/ P/B=3.24, Semiconductors =24% of index
MSCI Singapore: 10Yr returns: 2.83, P/E=19.9, P/B=2.83, Banks=35.17% of index
Based on a simplistic analysis of the above I would say that Korea is the best buy. Buffet seems to agree and has picked up some shares in the steel major POSCO which is 7.6% of the Korean index.
In Singapore you can buy the Lyxor Korea ETF , in the us you can buy EWY.
Disclaimer: I already own the Lyxor Korea ETF and am invested in a Singapore Index.
I am not sure if the numbers above include reinvested dividends. The P/E also seems to be different from other estimates I have seen, possibly because they may be using only annual figures and not TTM and also because the more bullish analysts usually mention forward P/E instead of trailing P/E.