Dunno, but I can tell you what my experience was when using data on my phone with the PCCW SIM (purchased from 7-11 for HKD 48).
- I used it in my iPhone 4 (it came in a break away microSIM card, but if you want standard SIM card that's ok too - just don't break out the microSIM)
- with 3G data enabled speeds were very usable (can't say I tried to download anything massive to test speed), but:
- - emails came down ok;
- - browsing websites seem reasonably quick (even this DB + forum);
- - apps using the net were responsive (e.g. the HKeTransport app);
- - in fact, I was aboard the Airport Express and so I was moving when using the HKeTransport app to work out my trip details (so no issues with coverage whilst moving in train);
If you're looking for another discussion on the benefits of certain carriers in HK (esp. data oriented) see here*:
http://forum.sex141.com/eforum/v ... id=37015&page=1
* I contributed some info about PCCW and Three at post #10.
Hope that helps.