I didn't have any problems with my old BT GPS in China, I don't think it took particularly long to get a fix (I had just arrived from Europe). However, when I went way south to Australia my GPS never locked. I let it run for up to an hour several days in a row but never got a fix. Strange that. I emailed the vendor and asked if there was any known south-of-Equator problem and got a nonsense answer back (as expected).