traffic data

I bought my nuvi just because of the traffic feature. I was one that thought that if you needed a GPS, you shouldn't be driving. I'm now a convert and wouldn't be without it.

My driving is mostly Long Island and New York City area. We have 3 radio stations that give live traffic every 10 minutes during commuter hours. I've found the traffic data on the nuvi to be no better than radio information. It is no more 'real time' than radio and about as inaccurate. The most disappointing aspect of the GPS data is the amount of highway road space that shows 'no data'. I've complained about this to clearchannel.com (the provider) and they have only responded with excuses and lip service.

As far as your specifics, the provider monitors a slew of sources. In NY we have real time camera feeds and road sensors. I assume they compile a lot of info from DOT sources and maybe other sources. Updates are transmitted on FM radio channels (I think the MSN version does the same). The receiver is your subscription device, not the GPS; so if you have multiple GPS devices that can attach to a GTM-20 receiver, you can use any of them with the one subscription at any one time. You see road conditions a good (green), not-so good (yellow), slow (red) and no data (no color). If there's an accident, it says so. I don't know about events.

I'm interested in the Dash product. If it gives better traffic, I may upgrade. Hope this helps.

Thank you for your answer.
I knew someone who worked for a traffic provider for the radio/tv stations. His source were phone calls, the local police and the state police's website. Not accurate by any means. Our local news radio station says, "If you're not seeings what we are saying... CALL US!" So if the sources are the same it isn't going to be accurate.
My biggest concern are closed roads, or construction delays. I really don't need a GPS to get to work. My commute at one time was 38 miles, there was construction and accidents and I knew enough to travel in the right lanes of the highway so if I needed to I could get off and take the regular roads. Now my commute is less than three miles. I can walk, take a bike or drive and when there is a delay the other route is easy enough to get to.
I am more of a techy for this and would like to know if and when I go on a business trip if it is worth it? But if it is no better than the radio station then I guess not.

This link is to an article that does a fairly good job of describing how the TMC traffic data is collected. The TMC traffic is not dependent upon physical, like in-road loops, cameras, etc. to collect data and appears to have a very good data collection system.

http://www.gpslodge.com/archives/007617.php

Bill

For example Sporting events Like Nascar or the Cowboys games or other events such as the State Fair, even the recent Hanna Montana concert. The details page will state "Spectator Event", if I remember correctly, the symbol is a blue circle and white stripe.

If I were traveling through this area when the Hanna Montana concert was going on (or the state fair)...would I have really known that? I don't think so, especially if in unfamiliar territory.

Some of the time if there is an incident or accident, the traffic details page will include which lane or lanes are open or closed.
I'm advised "entering slow traffic area" and that info too, is usually accurate.

The normal traffic status...is usually, fairly accurate and timely...but not always and it's far from perfect. It works well enough for me, I'll keep the subscription.

That's what I see here in the North Texas area.
I'm sure a lot depends on the specific area. I took a trip from Tx to NYC and back...where there was traffic coverage, it identified problem areas. Again, it isn't perfect, but tolerable.

I've never used TMC traffic since I have a Nuvi 680 with MSN traffic. I have to say that the MSN traffic is not bad on my daily commute. Unfortunately in the Phoenix area, I can be well into my commute when it will report a problem and I'm already stopped. Every night when I'm getting ready to come home, I get in my car and turn on the GPS and check the traffic. I check to see how much is read and how many accidents there are. I pretty nuch know which way I'm going to go just from trying different ways every day.

On longer trips to unknown areas, the MSN traffic has worked flawlessly. I took my first trip to the LA area a few months ago. I was traveling down the Interstate and it started recalculating. It turns out that the GPS routed me around a traffic heavy area. At this point, I wouldn't be without the traffic just for the trips I may take outside of my immediate area. I will keep my subscription.

It would be interesting to hear how the TMC traffic differs from MSN.

I would agree that your comments and conclusion regarding the MSN traffic are also true with the TMC traffic. I saved an hour on a normal 20 minute trip on my first use and the value of this device in cities where I am not familiar has been remarkable.

I have read that the TMC might give some information quicker and have more widespread information, but it does not have the gas, movie and weather information. I really can't do a head to head comparioson without using MSN, but you certainly seem as pleased as I am with TMC.

Bill