Good question Bracke.
For most of the time, I think speed limits are a good thing.
However, the problem with our police in my view is that they do not exercise discretion.
For example - one Sunday morning at 5am (couple of years ago)I was stopped by an unmarked police car on a stretch of deserted dual carriageway (the A11, if you're interested). There were no other cars around (except him of course), the roads were dry, it was clear, straight stretch of road with visibility about 3 miles.
I was driving a bright red Ferrari F355, doing 90mph, and he nicked me and gave me 3 points and a £40 fine. Admittedly I was speeding, but some discretion would have been nice.
Personally, I thought it was a case of him being a bit of an a***, and not liking my car or the fact that I was a lot younger than him.
Now, if you go to, oh, I dont know, Canada for instance - they aren't allowed to have speed cameras in Ontario because its considered to be an infringment on their rights - which I happen to agree with.
I think the biggest problem with the so called "safety cameras" in the UK is that they are in fact nothing more than a big fat cash cow for our Police Force, and the majority of the public (including myself) resent the fact that they're littered all over the countryside in places that are not, and have never been, "blackspots".
So, yes I think speed limits are a good idea.
Speed cameras however I think are a bad idea.