Went on long trip in March. T-mobile worked flawlessly in:
- Bangkok, Thailand
- Siem Reap, Cambodia
- Hanoi and Halong Bay, Vietnam
- Kuala Lumpur, Malaysia
- Bali
- Singapore
- Seoul, Korea
- Osaka, Japan

It actually worked better (signal wise) than most of Northern California. Speed was slow but usable.

Very happy with it. Would switch over if they have better Nor Cal coverage.