About a decade ago diesel was so much cheaper than petrol and with diesel cars burning less fuel it made sense to buy a car that runs on this fuel despite them being more expensive, but with the diesel prices now being at the same level or more expensive compared to petrol what's the point of buying a diesel car? Sure, their engines are capable of pulling heavier loads, but the regular Joe doesn't really need that. There's also the issue of diesel cars emitting more polluting particles. I've read Paris (France) aims to get rid of all diesel cars withing the city in about a decade. I reckon diesel cars are on their way out.
Actually, in many places diesel is significantly cheaper then petrol. For instance in my region, it's 30 cents cheaper per gallon. That's crazy! Not to mention, diesel engines tend to be more efficient, so you double-save, as not only is the fuel cheaper in the first place, you also have an engine that uses less fuel per 100km. Petrol prices have gone down but they will surely go back up again the more the general economical situation improves. If you live in Saudi Arabia or the United States, petrol is very likely more worthwhile as it's very cheap in those countries, but in most places in Europe, diesel wins in fuel economy by a big margin.
Here in the UK diesel is around 5 pence per litre more expensive than petrol but i find it is still more economical to run a car on diesel. My girlfriend has a diesel car and i have petrol, if we go on a long journey we will always take my girlfriends car as we will typically save a third on fuel costs than if we had used a petrol vehicle. Road tax is also cheaper for diesel cars here as the taxation is based on emissions. Diesels burn less fuel than petrol engines so are considered more environmentally friendly, although diesel itself is not considered one of the cleaner fuels.
@JulianWilliams I had no idea France wants to rid the country of diesel engine cars. That's newsworthy! @CrimsonAdder , I can attest to your point that diesel is cheaper then petrol as in my little country, for this time, diesel is significantly cheaper then petrol, and I mean, significantly cheaper! and to be fair, I have always known diesel to be cheaper! I have a car that operates on petrol... a Suzuki Swift, and I get really good service from it! I think I would have been worse off with a diesel engine, because the mere fact that the diesel engines are bigger, they consume more gas, so I definitely would have to visit the gas station more often if I had a diesel engine as I drive very long distances every day!
The price of buying one as well as of maintenance, insurance. and repair is often more. In that case, it's not always a bargain. Nonetheless, it's something to consider as there is significantly better gas mileage for highway driving - and it's better for the environment.