Accuracy of ETA feature
from Seattle to Redwood National Park via US-101. I thought that this could be a chance to try out the new ETA feature. I brought my latest Garmin Nuvi 660 to compare 
When I was half way there, I turned on my Garmin to compare the ETA. Surprisingly
(or not surprisingly) there was 3 hour difference between two units. When I arrived at the destination, it turned out that it was the Mercedes Nav which was off by 3 hours(It said it's gonna take 3 hours longer than Garmin). What a disappointment! I hope
that there is more updates soon which could provide the better accuracy on this convenient feature.
Last edited by Heejin; Sep 13, 2007 at 06:36 PM.

I assume the MB system giving a pessimistic estimate, they have to take care of the liability issues and should not encourage people driving too fast.
I've seen similar accuracy on my W221 ETA as George explained. The system cannot estimate if you will be driving a lot faster/slower than average on that road, if you had been driving 3 hours differently, the MB would have been on the spot and Garmin 3 hours off

Did you read the ETA before starting the trip or during the trip? I'm not sure but I assume the car takes into account "the speed so far", if you happen to drive slow first, it would assume the same for the rest of the trip.
I assume the MB system giving a pessimistic estimate, they have to take care of the liability issues and should not encourage people driving too fast.
I've seen similar accuracy on my W221 ETA as George explained. The system cannot estimate if you will be driving a lot faster/slower than average on that road, if you had been driving 3 hours differently, the MB would have been on the spot and Garmin 3 hours off

Did you read the ETA before starting the trip or during the trip? I'm not sure but I assume the car takes into account "the speed so far", if you happen to drive slow first, it would assume the same for the rest of the trip.
Last edited by Heejin; Sep 13, 2007 at 06:37 PM.





