Tokyo rocks, lived there for 5 years.

Avoid Singapore though, you will get bored after a few months and its EXPENSIVE.

The best schools in Singapore by order of package/reputation/facilities and good education are:

UWC
SAS
Tanglin
AISS
GEISS
Dulwich
Dovercourt
One World
OFS
Nexus
ISS
Chatsworth

Just a heads up for everyone here. I have a few friends who work/have worked at Chatsworth International School, Singapore.

Avoid this place at all costs. They are focused on making money and nothing else. No resources, building falling apart, weak admin, low pay and long hours. You have been warned!