Nothing has gone wrong with this car since I have owned it. I have put it through an extensive routine service including replacing clutch and fuel cell (a requirement after 7 years). The service was done about 2 years ago, and the car runs beautifully. If it is not driven for several weeks, it tends to develop a small oil leak which I think is from one of the cam seals. But after driven for about 15 miles, the oil leak is no longer apparent. If the car is driven once every 2 weeks (about 12 miles each time), the oil leak is not present. The oil pressure in the car remains normal at operating temperatures.
The XJ220 is in my opinion the most beautiful car ever built. I still marvel at its beauty--often examining the car from every angle to take in its artistic form.
The performance of the car is awesome. It is deceptively fast, by which I mean it accelerates so smoothly and without effort, if not careful your at some pretty ridiculous speed in seconds.
The sound of the car--a point which has been criticized in the past-is very impressive. It is very quiet and mechanical at idle, but when you drive it at 3200 - 4000 rpm you can hear a high pitched exhaust note similar to the group C cars. I used to own a Ferrari F355 which had a great sound, but I like the sound of the XJ220 at speed better.