A bit of background to help frame my take on the XF: Nearly everything I've driven in the past has had two doors, and performance has always been paramount (past cars include an S2000 and a 328i).
The XF is clearly a departure. It's large, plush, and gadget laden. Still, the car certainly satisfies my need for speed. It strikes a solid balance between the ability to carve canyons and coddle. I've been a die-hard BMW fan for years, and the decision to throw my hat into Jaguar's ring was the product of considerable research and multiple test-drives against the 528i (similar lease rate). The 5 is a fine car, but the Jag is more car (and more muscle) for the money.
5.0L motor makes serious power and an intoxicating sound, herculean brakes, chunky steering wheel, comfortable seats, beautiful detailing inside and out (stitching on doors/dash, brushed metal galore, tiller's thumbwheels, supple leather, satin wood trim), Aston-like contours,
large trunk, base model comes heavily equipped (the car is a relative bargain), voice controlled navigation/audio/phone work beautifully, rare.
Steering is a bit light at low-moderate speed (matter of preference), standard 400W audio system is atrocious (bass is nonexistent and treble is generally shrill), touchscreen is a bit slow, base seats lack much adjustment, HIDs aren't as good as those found in comparable cars.
As an aside, my car has 500 miles on the clock and it creaks like an old ship. Sounds like some seals need lubrication or replacement (moonroof and doors). There are also some interior rattles.
Jaguar service is light-years behind competitors'. I haven't found a dealer that issues Jaguar loaner cars (they use Enterprise, whose locations close at 6 and make after-hours service nigh impossible).