SoCal,
I hear your concerns. I can give you an example of FCBs that i know directly. I know that Koreans make up the second largest Asian population, next to the Chinese in Irvine. My good friend's aunt sold a small apartment in "Ap gu jong dong" a prime location in Seoul for around $2 million and bought a home in Northwood Pointe with 100% cash down. They both live off of the real estate income from their other real estate holdings in Korea, and both do not work in the U.S. My cousin's husband is one of the top plastic surgeon in Seoul who also owns several apartments and medical buildings in Kangnam, one of the most expensive real estate in Seoul. For example, The per square footage in Kangnam is more expensive than the prime real estate in Manhattan. She told me that two of her affluent friends have bought a house in Irvine (100% cash) to send their kids to University High. Recently, I read in the Korean newspaper that they are now marketing one week House Hunting Tours in Los Angeles and Orange County where affluent Korean buyers are bargain hunting. I have also read that getting a traveler's visa has become much looser than before, which should open up floodgates for more immigration into the U.S.
I don't really know much about the Foreign Chinese Cash Buyers in Irvine so i can't really make any comments about them.