I have had one for three years now. Love it dearly.
Its a really reliable car, and goes like nothing I have had before. I catch myself bracing for acceleration while driving my wife's 3l Toyota, and then just looking stupid.
I call it point, and squirt, the diesel has tons and tons of torque, and overtaking is a fun thing to do.
Couple of points.
It's a diesel. People tend to drive them like petrol cars. That's where you hear all the horror stories. Don't go over 3000 rpm. You are just making more noise and using more fuel. She red lines at 5, but 3 is the sweet spot. Over 3000 and the engine starts straining and the internal temperatures start soaring. I have experimented with it, and found that up to 3000 RPM the exhaust temp stays constant at about 600C. At 3500 RPM it went up to 800C and just kept going.
It requires a bit of a different driving style and philosophy. I often stay in 5th gear while overtaking, she has the power.
The turbo must get a chance to cool down. Running speed is 100 000 RPM and idle is 30 000 RPM. If you run her hard and then switch the engine off, you will be cutting off the oil supply and the bearings will seize very quickly. A disintegrating turbo sends spare parts down wind, which is where your engine is, and engines don't like solid pieces in them, and it gets expensive.
I live just off the highway, and just keep the engine idling while opening the gate, driving in, opening the garage and letting her coast in. About half a minute of idling is enough. The modern turbo's are reliable, and don't give trouble, but just remember its there.
The service interval is every 10 000 km so the running cost is a bit higher, but it is offset by cheaper fuel ( in South Africa, don't know about the UK)
If you drive like a hooligan with all the torque she has, you will be buying tires often. My first set lasted 6 months, my current set two and a half years, and still have plenty of life.
She goes up to 130kph and not much more. The engine sits at about 3000 RPM at 120kph, and as mentioned above, its not too ideal.
the fuel use at 110kph about 5l per 100km. At 120 its 6l per 100km. Tested on several 3000km+ holiday trips.
Fortunately anything over 120 kph attracts the attention of the traffic guys, and they don't have a sense of humor, so 120 it is.
My brother in law has a Diesel VW Tiguan. His turbo went spectacularly, one morning about 300km from my place. I went out there to tow them back. The VW weighs twice as much as the Micra, and I towed him back at 100kph, average speed, at a fuel consumption of 5.2l per 100 km. with the aircon on.
Its a great car, I wont swop it for anything. The only thing she needs is cruise control. I miss that on the long distance trips.
Good luck