A few electrical problems, which took care of themselves by just driving the car.
When I bought the car, the second day with it, the ABS fail light came on, check engine light came on. I just kept driving the car, and the ABS light went out, and has never come back on.
I pulled the codes for the check engine light, and I had a fuel vapor leak (gas cap) code kick out. No big deal. If I leave the cruise control button on for too long, I get the engine failsafe mode light, the car doesn't run any differently. So I just turn the car off, turn off the cruise control, restart the car, and the light is off. Probably something with the cruise control part of the throttle body, it doesn't concern me.
If you're anal, don't buy a Jag, me having owned an XJS/XK8, and now an XKR, as well as working on aircraft for 15 years, electrical problems don't bother me. A lot of them can be-caused by certain humidity/intermittent relays/pressure conditions. You can spend a fortune trying to trace these niggles or just drive the damn thing, and they work themselves out.
The car has a lot of power and handles nicely; it's not the XKR is that heavy, it's that its CG is too high. I had an XK8 that was lowered, and this car could handle as well as any sports car. My '97 XK8 that I had was lowered with the 18" XKR rims fitted to the car, this thing stuck so good in corners, the front rims would scrape against the coil over and sparks would shoot out of the left front wheel well on a hard right turns, kind of scary when it happens.
Knowing how an XK8 handles lowered, the XKR would just be that much better lowered, because of the rear end set up, you can predict what it's going to do, and not just lose it. It's also not bad in the snow with all weather tires. Just turn off the traction control and that rear end will dig itself out of anything. Similar to my the old XJS.
As far as straight line performance, with traction control off, and the car in sport mode, it's really a different car. I was able to pull away (easily) from an 09 Carrera 4S, which really surprised me, considering an 09 4S is about 500lbs lighter with a little more hp. We did this 4 times from about 30mph on, and each result was the same. I was also dead even against my buddies 06 CLS 55 AMG, from about the same speed. From 30 to 120 I get the jump on him and we're dead even, and then at 120 he pulls on me. The exhaust note is almost non existent, which is fine by me. There's something to be said about quiet power.