Downloaded and installed Nav4All on my E71. It is free, and therefore utter garbage. They plan on charging for it, at some stage, but it will need a lot of improvements.
Taiwan maps are from Q3 2007, so slightly outdated, the usual lack of minor street names (like Nokia maps), a very slow GPS lock (I set for for 3G a-GPS, but I am sure that it is still using the internal GPS). A cumbersome menu and search setup, hardly any POI ( even less than Nokia MAPS), and maps are hosted on a server, so need to be downloaded each time your position changes or if you zoom in/out.
This has now been uninstalled.
Garmon told me (after my multiple faxes and phone calls) that Garmin Mobile XT is NOT available in Taiwan, and Garmin USA told me (via phone) that the TaiwanMobile XT maps are not available in the USA?
So, I really do not have a clue how to actually get a legitimate copy of this?
MapKing advised me via email that they are not planning on releasing an English version of their Taiwan map for S60, because there is not enough demand.
I do hope that in time Route 66 will add an update for E71 compatibility, at this stage their product looks like the best alternative for GPS on Symbian devices.