Hello everyone, I'll be heading to Canada in September for university and I would like to buy the upcoming iPhone 4. I have a few questions which I hope you guys can help me answer. Thank you very much! 1. Are the iPhone's sim-card locked in Canada? 2. Because I live in Hong Kong currently, and buying the phone would be tax-free and they're unlocked, would it be wise to buy it here and sign up to a contract there? 3. Which phone network is best in gaining signals?