I'd say everybody who hasn't used the system yet keeps it down a bit.
I experiencee the Speed Limit Info in both the F07 535i GT as well as the F10 523i and it helps a lot.
Especially in Germany, where you have Highways with no speed limit, or often also with 130, 120 or 100 km/h it's really helpful and avoids you driving 200+ km/h in a 130 section.
It's also helpful in cities you don't know yet.
So what are you complaining about? The acutal "warning" of the system? There is no visual flashing or a alarming sound or whatever.
You just see the current limit in the HUD (which can be deactivated) or in the speedometer (which can be changed to whatever you want via the BC button).
In a nutshell the system in combination with a head up display and the "German Autobahn" really helped a lot. And there is nothing more satisfying than seeing the sign of "all speed limits end here" in the HUD in front of you as you go 250 km/h