Funny old thing Kris... In 2006 approx 33% of new car sales were diesels (nearly all turbo-diesel). Here are the cars I've owned since Nov 2003 with MY views:
Nov 2003 - new Mazda RX-8 231: 18 mpg & £650 insurance(!!!) - it lasted 6 weeks for me... Changed for brand new VW R32 Jan 2004 - 22mpg & £650 insurance. I kept that for a year but had a TDi 150 as a courtesy car for a week & swear the TDi was faster in the real world of overtaking power on country roads.
Smart Brabus Roadster: 50 odd mpg, £115.00 insurance but ran out of guts above 80mph.
Audi TT225 Quattro: 32mpg, £350 insurance. Great quality car.
Lotus Elise S2 last year as a second car: 40 odd mpg but it sounded like a tractor!! It lasted 8 weeks.
July 2006 - BMW 3.0SE AC Schnitzer Z4: 32mpg, insurance £215.00. Fantastic mpg for the performance. Sold it in August 2007 & bought my first ever diesel (I'm 50) - A GPS 130 Punto: £140 insurance.... Very very impressed with the smoothness, performance & hilarious economy - but not so with the hard shiney plastic low-rent interior or the rubbish "Blue&Me" voice activated system - that refuses to understand me - a useless gimmick. So much so that I fitted a Dragon Performance box last week, pushing the bhp to around 170. I've only had the Punto for 2 weeks yet decided that I will never go back to a petrol engined performance car. It's a no brainer! - lower road tax, much lower insurance, better real world performance & more than twice the mpg of equivalent powered (BHP) petrol cars.
In fact, I've just bought a 200bhp JTDM Alfa Brera SV. My Dragon Box is being re-mapped today to give 230BHP (min), 400nm torque & 44mpg..... That says it all. I'm afraid that technology has come on leaps & bounds & with a turbo-diesel we can totally transform the driveability, enormously upgrade the BHP & Torque - yet with massively improved MPG for less than £300. Work out what a 30-50BHP gain on a petrol engine costs! - Upwards of £2000.