As the title says, which one is the better ?

ESRI.

+1 ESRI

Use ESRI now for 3 years, reliable.

I'm using ESRI also for years, but can't say it is reliable, as sometimes I get directed through very small back streets.

I was always told that Tomtom was so much better, and I believe that their maps are from Navteq as well.

In settings from my ESRI Garmin device, you can choose to eliminate the route by shortest distance instead opting for using main roads only, have good experience with that. I should maybe add I never use the address function itself, as I indeed encountered erroneous directions.

Instead I look up my destination in Google Map, get the coordinates and use them as input for my Garmin with Esri.

Travelled through Thailand from North to South, only few errors.

A problem I experience a lot is that at places where there is an elevated highway that it thinks I'm on the highway when I'm not and vice versa.

When I enter the elevated highway Chonburi - Bangkok for instance it will tell me that I'm on the ramp, but as soon as I pass the toll booth it shows me downstairs again.

This goes on until I've passed the Bangna entrance, after which it locates me above.

A problem I experience a lot is that at places where there is an elevated highway that it thinks I'm on the highway when I'm not and vice versa.

When I enter the elevated highway Chonburi - Bangkok for instance it will tell me that I'm on the ramp, but as soon as I pass the toll booth it shows me downstairs again.

This goes on until I've passed the Bangna entrance, after which it locates me above.

This has to do with the vertical accuracy of your navigation device and is AFAIK not related to the map system.

A problem I experience a lot is that at places where there is an elevated highway that it thinks I'm on the highway when I'm not and vice versa.

When I enter the elevated highway Chonburi - Bangkok for instance it will tell me that I'm on the ramp, but as soon as I pass the toll booth it shows me downstairs again.

This goes on until I've passed the Bangna entrance, after which it locates me above.

This has to do with the vertical accuracy of your navigation device and is AFAIK not related to the map system.

Why does the vertical accuracy change when I'm at the Bangna section ? Is there any way to adjust this ?

A problem I experience a lot is that at places where there is an elevated highway that it thinks I'm on the highway when I'm not and vice versa.

When I enter the elevated highway Chonburi - Bangkok for instance it will tell me that I'm on the ramp, but as soon as I pass the toll booth it shows me downstairs again.

This goes on until I've passed the Bangna entrance, after which it locates me above.

This has to do with the vertical accuracy of your navigation device and is AFAIK not related to the map system.

Why does the vertical accuracy change when I'm at the Bangna section ? Is there any way to adjust this ?

What kind of personal navigation device do you have?

A problem I experience a lot is that at places where there is an elevated highway that it thinks I'm on the highway when I'm not and vice versa.

When I enter the elevated highway Chonburi - Bangkok for instance it will tell me that I'm on the ramp, but as soon as I pass the toll booth it shows me downstairs again.

This goes on until I've passed the Bangna entrance, after which it locates me above.

This has to do with the vertical accuracy of your navigation device and is AFAIK not related to the map system.

Why does the vertical accuracy change when I'm at the Bangna section ? Is there any way to adjust this ?

What kind of personal navigation device do you have?

Garmin Zumo 550

That's a great PND, JesseFrank.

I think that when for one or the other reason the vertical accuracy cannot be better than 6-8 metre, the PND will mistaken the elevated road for the road under it. It's just the way it is.

That's a great PND, JesseFrank.

I think that when for one or the other reason the vertical accuracy cannot be better than 6-8 metre, the PND will mistaken the elevated road for the road under it. It's just the way it is.

The strange thing is, it tells me I'm on the entrance ramp of the highway, as soon as I on top it says recalculating and places me on the road under again.

In Don Muang it's just opposite. I drive on the road below and it places me on the highway.