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Another thing people overlook when ranking the "best" GPS is fact that maps differ from country to country.

Navigon in Australia uses map that is probably at least two years out-dated, and has no speed information. POI is really the most horrid I've come across.

Tom Tom Australia is probably the best choice in this country, just surpassing Sygic, but using it in Asia is not possible since there is no map for it. Sygic is the only candidate in South East Asia ATM.

Tele Atlas is not always the best map in every country. Similarly Navteq is not the best map in every country. In some countries, they partner with other smaller map providers, and the quality differ from country to country.
 
Fedorov:

You can adjust the voice instruction lead time in CoPilot live. Default is 5 seconds before the turn. I've found that 6 to 7 seconds works well.

Thanks - tried on 7 seconds on way home tonight, turned left at a roundabout and my street is then 200 yards on the left, it started telling me just as I was almost on the turn so I've increased it to 8 seconds and see what it is like next time I take that same route home now I've found a spot where I know it needs to tell me quicker :)
 
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