I finally had a chance to drive two 2007 XKs on same roads I use my XKR on. One 2007 was a coupe and the other a convertible. It's a value proposition for upgrading whenever that day may arrive in the future.

The question I wanted to answer was, how do they compare in the city and sub-highway speed curves?

While the newer cars have the faster shifting 6 speed ZF transmissions AND fabulous paddle shifters that allow shifting down into first after being in higher gears, the supercharged 4.0 litre is still noticeably more exciting in pure acceleration from a standing stop and passing power. Probably a big difference when climbing steep upgrades at highway speeds but that is a rare treat for me to get to.

However, when diving into tight corners, the newer models transmissions and paddle shifts down to first enable slick, fast transitions that the prior models cannot compete with.

A superb 2005 coupe I drove along with mine proved most exciting of all but at the same price as the 2007-2008 non-supercharged you'd want to choose based on where you drive it.

Tight corners and canyons? Newer model.
City 0-50 blasts? Prior model with supercharger. Oh, and remove driver side fuse 10, as I did during these tests, and the older car's steering feels much more sporty and not inferior to newer versions. Whew, that solves my curiosity!

Final note of practicality. Baby seat is viable in prior model behind passenger seat, not so in newer model, even for the coupe.