A mapper who tried to map houses with osm2go (and who politely offered the above screenshot) asked whether the GPSr’s accuracy of the N900 was poor. The above screenshot suggests it is. For a couple of reasons, I doubt that the result would be (much) different using another device:
- GPSrs are usually optimized to provide more accurate positioning data during movement. While moving slowly (e.g. as a pedestrian), you will see worse results regardless of the receiver used.
- GPS reception is poor near walls. This behaviour also applies to devices like the WBT-201 or Garmin’s GPSMap. If possible, try to use a bike. Ride straight intersecting lines passing several buildings in one go instead of moving around each individual building.
- Mapping house numbers in cities by foot usually requires some guesswork when entering the data after the trip. The set waypoints usually are offset by several meters.
I’m using the N900 for over a year now, and I’m very content with it, as I was aware of the aforementioned issues. It is a bit inaccurate while hiking, but on the bicycle it’s almost perfect.