Help Does Unlocked HTC Desire Telus work in Asia?

[moonflower]

Hi everyone, I'm new to android phones and will appreciate some help. I'm interested to get an unlocked htc desire from telus, but I have a few questions before I'm going to get one: 1. Will the Telus HTC desire work in Asia (esp. Japan, Hong Kong, China)? 2. What are the differences between htc desire a8181, a8182, and a8183 series? 3. Can I get updates if a new os is out, even if I'm not with Telus? Thank you in advance. Cheers,