At last, a Jaguar that not only competes with the premium Germans, but also looks forward far enough to make it a plausible match for whatever über-saloon they'll come up with next.

The XF has already snaffled enough plaudits to make it feel like the next stage in an actual rennaissance (the XK was the first stage), rather than another dreary false dawn. There's a real sense that there's more going on here than just the slightly gimmicky interior on which much of the XF's puffery has been hinged. Good vibes.

But if a car is only as good as its engine then this, the V6 petrol unit, is a heel Achilles himself would be shamed by. It doesn't match the rest of the Jag experience. Sure, it sounds great when you really stretch it - there's enough noise to be pleasant, not too much to make it hard work - but you really do have to push it to extract its best.

If you mash the accelerator into kick-down territory, it's a reasonably quick car. But if you don't go beyond that point - and let's face it, constantly flooring it soon gets tiring - then you're left wanting. Over an empty back road, it's much worse. The V8 doesn't suffer from this.

The upshot is that fuel consumption rises alarmingly and, without having done a back-to-back test, there's a general feeling within Top Gear Towers that the V8 might actually be slightly more economical in the real world.

Which is a shame, because the XF drives wonderfully. It's very nimble around the nose so turns in sharply, and has enough feel through the chassis and steering to make it an enjoyable drive. It's no sports car, granted, but way more involving than dull cars like the Mercedes E-Class.

The ride quality, however, still has some work to do. 18-inch wheels are standard with this engine and trim, but our car came on 19s. I still haven't driven an XF on 18s, so can't tell you whether that's the way to go, but on the bigger rims there's too many road imperfections coming back into the cabin. It's simply not as smooth as it should be. Obviously it rides a whole lot better than any BMW, but for an executive car, it isn't good enough.

All of which doesn't stop the Jag feeling current, but with a V6, the Germans are still ahead.

Piers Ward