Without a doubt a 5 at this point. Seven months old, 5,500 miles. When people ask me if I've had any problems, I tend to be unable to think of anything even if I try. One small annoyance is the tire pressure indicator, as the allowed range seems to be close to the accuracy tolerance of the gauges.

Smooth shifting in first and second gear seems to be an impossible goal, as my passenger typically does a lot of head-bobbing. I also had it pop out of third gear once, which was a disturbing experience. This was during hard acceleration into 55 mph traffic from a dead stop, and I suppose I didn't fully get the stick into the slot.

My XF is an '05 Aero Blue/Vanilla limited roadster. I didn't care for the mapless stock nav unit (I didn't even test it), which I sold on ebay and replaced with a Sony mp3 CD unit. They have an aluminum finished model that matches the console well enough, in case anyone is interested. The display text is blue, though.