Re: Sat navs..
Posted: Wed May 13, 2009 6:41 pm
The product is as good as the map after the base technology (this is not typically proprietary but a licensed chipset) is taken into account. I find the Garmin maps have minor issues where roads have been mildly rerouted, but it's fun to drive "across the field" or to see where the road used to go. Note that your vendor is likely to have a better map for its own country.
As to right turns on motorways, one common issue is synching to the road either underneath or beside you. There's a distance algorithm used for this, but remember that on crossroads, the system is essentially two-dimensional.
I've used three different kinds and all were about equally accurate. Common annoyances:
- Listing the town or city twice, once followed by "twp". The person writing the map code didn't bother to reduce these to one place (which they are) so you sometimes have to search both for your road. Ditto for spelling variants Marlboro vs. Marlborough and similar stuff.
- Annoying off-route behavior (Garmin's is good)
- Inability to know how to avoid accident traffic.
- Nobody yet seems to have issues like road restrictions (e.g., no trailers) built into their algorithms.
In the U.S., Delorme is a mapping company and has excellent maps. Unfortunately, their product is really cumbersome to use.
My ancient Garmin Quest is still my favorite 'cause it works well in the woods and on my bike. I wish I could find a replacement battery for it.
As to right turns on motorways, one common issue is synching to the road either underneath or beside you. There's a distance algorithm used for this, but remember that on crossroads, the system is essentially two-dimensional.
I've used three different kinds and all were about equally accurate. Common annoyances:
- Listing the town or city twice, once followed by "twp". The person writing the map code didn't bother to reduce these to one place (which they are) so you sometimes have to search both for your road. Ditto for spelling variants Marlboro vs. Marlborough and similar stuff.
- Annoying off-route behavior (Garmin's is good)
- Inability to know how to avoid accident traffic.
- Nobody yet seems to have issues like road restrictions (e.g., no trailers) built into their algorithms.
In the U.S., Delorme is a mapping company and has excellent maps. Unfortunately, their product is really cumbersome to use.
My ancient Garmin Quest is still my favorite 'cause it works well in the woods and on my bike. I wish I could find a replacement battery for it.