Between the big 3 mobile telcos in Hong Kong, 3 Dualband (fomer Orange Dualband) is the worst of all. High drop out rates, weak signals, bad coverage and insufficient lines available in busy areas are the major problems. But they are welcomed by Hong Kong residents because they are simply cheap... cheapest within the big 3 I would say.

I would suggest anyone whose going to take advantage of the "3 Mileage Reward Program" to check the roaming rates offered by 3 and other telcos in Hong Kong before get sucked in. I always believe "There is no free lunch".

Keithl, regarding the roaming rate, I think it's best to check with your mobile service provider. Different providers and different countries have different rates.