Simon Clement (below) nearly got it right when he asked, "Who would buy a 150mph car when it was limited to 70mph?". My question is "Why is it legal to sell a new car with these capabilities?", especially when it is likely to use three times the fuel of an efficient small car. Perhaps some legislation to ban the sale of any new vehicle with a 0-60 time of less than 15 seconds, a top speed greater than 85mph, and average fuel consumption of less than 50mpg might be more appropriate. This would still give manufacturers plenty of scope for new designs. Chas Botfield, Luton

Before this idea goes any further, thus involving more law enforcement officers, why not make even a slight endeavour to stop people driving using mobile phones. And, let's have some action to stop the ever-increasing "overtaking" at high speed on an inner lane on motorways - an activity pretty rife round here on the M6. James Stuart, Chorley

Why not limit us to zero miles per hour. No deaths at all from speed. Here's a question: How often do you get to commit the mortal sin of speeding? I'd be grateful to reach the posted speed limit most of the time. Kevin Brown, Kettering

Speed limiters should not become commonplace; in fact they shouldn't be needed at all. Speed, and the ability to accelerate quickly can be very useful. This, however, doesn't stop poor drivers from hurting people. What should be available is a distance limiter to stop tailgating. This would, however, need a temporary override button to allow overtaking; a derestricted time slot of, say, 15-20 seconds so you can approach the rear of the car in front just before pulling out to overtake, thereby allowing you to use the power you are still allowed in your car and overtake quickly, thus not causing any overt danger. Name and address withheld

I believe that irresponsible drivers cause the majority of accidents. Drive at a steady 45m/ph whatever the road or traffic conditions or speed limit. This applies as much to 60m/ph trunk roads as it does to the 30m/ph through your local village. Many is the time I've been stuck behind Mr or Mrs Magoo on busy main road only to be left trailing their exhaust fumes as they storm obliviously through residential areas. Enforcing insurance obligations via visible discs (as in France), road Tax and MOT requirements are not soft options as drivers who avoid these may well cripple a member of your family without recourse. I also agree that speed limits should be flexible - upwards and downwards. Clive Laband, Haywards Heath

I think these limiters could be an excellent idea. As I often take my car across to mainland Europe and drive on the German autobahns, I would be interested to know what a safe maximum speed would be for these roads. The Germans seem to limit many of their cars to 155m/ph already, though this could be a little high. How about 145m/ph? Aaron White, Surrey

I firmly believe that any measure to limit speed is a good one. There are so many foolish drivers who speed up and engage in the unconscionably impolite, not to mention incredibly dangerous, act of hanging a foot or two off the rear bumper. Once imperilled in this manner, all sorts of misdeeds may occur, not just wrecking one's automobile. To wit, a few years back a church deacon signalled just such an offender to pull over. The fellow obliged the deacon and pulled to the curb, alighted from his vehicle, and was promptly shot by the deacon who wielded a crossbow. The offending fellow, struck in the chest, later died in hospital. This may be described as road rage of worst kind. I daresay that this tragedy would have surely been averted had local government been capable of remotely controlling a car's distance from another car, and its ability to accelerate. Under most circumstances, driving requires an impartial and unimpassioned foot on the accelerator, administered by those empowered to maintain public safety. Donald Abodeely, Massachusetts, USA

I agree that a manual override should be in the hands of the driver - once that individual has been taught to drive. ABS is not required if one knows how to brake properly, also automatic transmissions are a pain here because you can't lock it up into, say third, to prevent wheel spin. There should be a way of overriding that too. The most useful attribute for a car today is that quick acceleration that gets you out of trouble - 150 m/ph is no longer needed, but for merging and avoiding problems it can be a lifesaver. I know - I used to drive an E-type in England back in the 1960s and the acceleration saved me then. With the congestion today, it's even more vital to have that 0 to 60 figure. Pat Doyle, Edmonton, Canada

Instead of handing out fines to those convicted of motoring offences, why not force the offenders to pay to have speed limiters installed? While our government spends billions of pounds of our money fighting an elusive war on terror, with 3000+ road deaths and 200,000+ serious injuries and most people too afraid to venture out on foot or bicycle, the true terror is right outside our front doors. Action taken to limit the use and speed of the private motor car would have great benefits to the economic well-being of our country and all of our standards of living. Before all you dinosaurs start to rant about freedom of choice, just ask yourself how many hours you have to work to pay for your motoring "pleasure" and how many people yearn to live next to a busy road or holiday at a motorway interchange. The fact is, you have been brainwashed by billions of pounds of advertising to attach status to your shiny tin box and hate the thought that anybody should try to limit your pathetic attempts to impress with the potential for speed and danger. I take encouragement from history by noting that the equally ridiculous (though less harmful) codpiece eventually fell from favour. Clive Stringer, Eggesford

Yet another expensive luxury to be paid for out of the half pension Mr Brown has left me with after his great pension robbery. As to its use, I will drive foot to the floor and rely on the speed limiter. Kill someone and a reasonable defence will be that the speed limiter decided it was safe, so who was I to argue as I am not allowed to disagree with it in the other direction. Driving these days - yawn. Staying awake is the next problem. David Cage, Highworth

Another study where the expected result is clear in advance, perhaps. No doubt safety-nazis rejoice at the thought. I suspect that both congestion and accidents could be reduced equally well by: 1. Banning bus lanes; 2. Banning all chicanes; 3. Banning all road narrowing schemes; 4. Prohibiting roundabouts; and 5. Banning the imposition of any measures designed to frustrate, financially penalise or generally make more difficult, the business and domestic use of the Queen's Highway. Five bans in one go. New Labour in all its oppressive forms should applaud such measures! Donald Tindale, Tyne & Wear

The grim adverts from the Think! campaign that used to run on primetime TV were much more effective in promoting responsible driving than this nonsense. If the government and insurers are serious about road safety, they'd better sponsor more of them. George Petrov, Windsor