I’ve answered a few questions about SIMs here on Flyertalk and people seem to appreciate the help. (I don’t promote any products, just try to provide information for travellers with questions, but full disclosure, I am not unbiased. I’m posting under my real name and am director of marketing for
Brightroam.com.)
My first comment is that when you read about a massive several thousand dollar roaming bill, its always someone using data at the roaming rate. China is a very competitive market and data plans are very reasonable: rate are comparable with US rates. So there’s really no need to pay roaming charges. (Even if you have a locked phone – and you don’t want to unlock it - it’s probably cheaper to purchase an inexpensive unlocked phone carrying a China SIM and tether it to your favorite smartphone or laptop, than to pay the roaming rate.)
It is possible to get a China SIM with a data plan before you leave. The main advantage is that the voice and text rates on the SIM back to North America, are lower because the Sims sold in North America are designed for North Americans. (Local SIMs are designed for locals and the rates for international calls can be quite high.) You may also find that ordering in English is more convenient. It’s possible to order monthly plans - for as many months as you need - it before you leave, eliminating the need to top up locally.
MiFi – or mobile hotspot - is another option if you don’t want to unlock your phone. It’s a particularly attractive option if you’re travelling in a group. (In fact, just I talked with a Flyertalk member who purchased a single large data plan on a SIM which he placed in a MiFI. His family then tethered to the MiFI. The family had voice only SIMs, eliminating the need to purchase a data plan for each family member. A little overkill for most, but a good example that with just a little bit of planning it is possible to use your phone exactly how you want – even if you want to stream videos – when you travel at a reasonable cost.)