[kevkaz]

I am not much of a fan of RTTI. Seems to be something BMW can brag about, but in the end it isn't all that useful.

I live and work just outside of Chicago and have found that the RTTI data is not so real-time after all. There have been a few cases where it suggested a new route due to traffic - all but once I have ignored the suggestion and found traffic to be completely normal. I usually drive at the tail-end of rush hour both to and from work, and RTTI reports traffic conditions from maybe 15-30 minutes earlier.

Tonight was the worst, and has driven me to make this post - it suggested a couple of completely ridiculous routes home, one of which would have nearly doubled my commute. I took my normal route and it was perfectly clear... enough open space for me to easily vary speeds as I am still in my break-in period.

It did help me once the other day, suggesting that I hop off the highway one exit in advance to avoid a backup (which at that point was worse than what RTTI was telling me) - however by then it was pretty obvious that I needed to get off the highway, RTTI or not.

Hope this helps anyone who is considering Nav in their next car. I like the nav enough and don't mind Idrive now that I'm somewhat used to it - learning some of the voice commands helps - but I know there are plenty of you out there that aren't so fond of it.

I think maybe I'll let BMW know about it, with hopes that they'll figure out how to push more current data to vehicles. I definitely would NOT pay for RTTI data in its current state.

[kevkaz]

anyone else have thoughts on RTTI? I can't be the only one...???

[Ninjaneer]

I don't have much to offer in terms of the detour situations. The RTTI itself has proven to be pretty accurate on my routes. I always check the traffic situation to/from work on the interstate and when it says "slow traffic" or "traffic backed up" it's been true, maybe not in 1 or 2 situations where I found traffic to be lighter. There were 2 times I noticed it said there was a wreck and authorities were directing traffic around it... but upon reaching that point on the map I wouldn't see any signs of an accident, but traffic was slow.

I haven't played with the detour stuff much but when I did check it out one time it suggested some odd back-roads that I wasn't too interested in discovering. Another time it gave an alternate route that looked accurate compared to one I know exists but rarely take myself. Maybe next time I have more time to get to work I'll take a detour just for the experience

BTW, the Nav price didn't change, so it's not like we're really paying extra for RTTI - it's included. The premium package is what went up on the 335i.

[tomswift]

I depend on it every day. I have two primary routes (same distance) and as I back out of driveway every morning I use the RTTI to decide which route to take. Seem fairly accurate in Houston so far.

The problem with being current is not BMW but the source of the traffic information. I used to have XM Radio primarily for traffic and it was less timely. Houston idicates 3 sources to select from. I have mine set to Auto but I understand you can very the source. Not sure if any are faster than the others.
Tom

[E92Dutchie]

It's OK. Most of the time the info is accurate, but sometimes it's a bit outdated. But the data is being updated quite regularly though. I haven't tried it with guidance turned on, so I don't know where I would end up during my regular commute, but just seeing the traffic backups on the screen while you're actually crawling along that same highway makes it all worthwhile.

[poiney]

Kevkaz,
My situation is generally like yours. RTTI informs me of slow traffic (double arrows) and reroutes me to a city street with stop lights whose distance is > 2x longer. I disregarded the recommendation, fortunately, and was able to do > 60mph the duration of the freeway.

I don't understand why the RTTI is so inaccurate, but I don't understand the methodology. If there is a good explanation somewhere that explains why this occurs this would be helpful (i.e., so I have a better idea when to anticipate garbage info).

[LEDZEP]

Keep in mind that as tomswift indicates, BMW does not provide the data - they just provide your access to it. This is a technology in early infantcy and will no doubt improve over time. Right now it is a 'bragging rights" offering.

It would be like blaming BMW that there are no good FM stations in Nebraska. They put the radio in the car, so they should be responsible for its content... nope.

The more auto makers that provide the service, the better the service will get - just like everything. There are already published plans to upgrade the data points and delivery.

[poiney]

That's why I want to understand where/how the info comes in. Note that when I look at the traffic speeds from the web, they seem to be more accurate than my NAVI, which surprises me, since I figured they would have been identical.

[pseto]

RTTI will be getting an upgrade soon to make it even more timely. do a search for the thread I started last month.

[lkevinl]

I like it, mostly accurate and useful to guestimate my route time.

[Alan(iX)]

RTTI is only as accurate as the reports being broadcast by local radio traffic reports.
RTTI has routed me around serious accidents, but it also has incorrectly thought there was a problem in other situations.
It is supposed to be changing in the near future to have more accurate traffic info.

[LEDZEP]

The infrastructure (if you can call it that) and broadcasts are from Clearchannel (the Wal-Mart of radio).

[MacAttack]

Sometimes they're accurate and sometimes they're not. ...it's better to have and not want, than want and not have....