With aGPS how much does the reception improve by? Let's say you are travelling in a larger city in the CBD with skyscrapers are you able to get a reception or do you still need a clear view of the sky? Let's say you are in a narrow street with market stalls and the like. Or if you are in a underground walk way trying to find your way around when it's very cold outside - think Japan/Korea Winter.
Cheers.