The fastest Jaguar XE, now even faster.Woah steady on, it’s not that fast. And it’s not an SVR either. No, this is £48,045 worth of XE S, the current top-dog (top cat?) XE, now warmed over with more power. A choice move: since the XE S arrived on the scene, Audi’s revealed a 345bhp S4 , BMW’s evolved the 335i into the more powerful 340i, and Mercedes-AMG reinvented the C43. If you want a 350bhp-ish six-cylinder sports saloon right now, you’re spoilt for choice.Power-wise, it’s comfortably ahead. The F-Type-borrowed supercharged 3.5-litre V6 has soared from 335bhp (as per the basic F-Type) to 375bhp (which is what the F-Type S gets along with). The Germans are all ten or twenty horses down. Like the Audi S4 and BMW 340i, the XE S uses an eight-speed automatic gearbox as standard (the C43 uses a nine-speeder). Like the BMW alone, it’s strictly rear-wheel drive (the others are Quattro and 4Matic). Add all of that up – not to mention a healthy 332lb ft of torque – and the result is 0-62mph in 5.0 seconds dead. In isolation, a quick car then – and two tenths faster than the BMW 340i – but it’s only a solitary 0.1sec nippier than the old XE S and an Audi S4 is three tenths down the road by this point. Raw numbers bragging rights aren’t the reason to covet this car.The actual experience of going down the road – the bit the numbers can’t tell you. An XE S in its Dynamic mode with manual gearchange paddles, full bore noise from the pipes and the sharpest throttle response is a properly exciting sports saloon. As a pure drive, it’s the best £50k-ish fast four-door, no question.The XE S doesn’t behave like a boggo saloon car that’s had a rorty engine accidentally dropped into the nose. You don’t get the impression, like you do in the C43 saloon, that the steering and gearbox are forever doing their best to keep up with a runaway train of a motor. It’s also nothing like as reserved as the 340i and S4, which feel very deliberately rowed back from their maximum, so there’s no treading on RS4 and M3 toes. The XE S is allowed to be extrovert. You get supercharger whine garnish over the blare from the exhaust, and some entertaining histrionics to accompany the gearchanges. When you’re really up in, the eight-speed ZF transmission finally feels as sharp as it does in BMW’s applications. As per usual in an XE, when you’re just pootling, it’s not as cleverly calibrated, and a bit lethargic. Where all XEs really shine is in that quintessentially Jaguar blend of ride and handling, flowing down the road with exceptional body control, steering with agility but without being overbearingly sporty or uncomfortable. It’s a very tricky compromise to pull off, but it’s always been the baby Jag’s ace in the hole, and the S just amplifies all that’s good about it. You’ve got masses of traction to lean on, the brakes are spot-on, it feels lively when you want, but never unstable. All the more reason to turn up the wick even more for a supercharged V8 XE SVR, then…Yep, it appears there’ll be a Macan Turbo rival before an M3-baiter from Jaguar. But you know what? That’s fine. What the XE S shows is that when Jag just builds the best car it can, rather than worrying too much about matching the Germans spec-for-spec, car-for-car, it can create cracking stuff. Sure, this thing lacks the all-weather appeal of two of its main rivals, it’s far too cramped in the rear and the visibility isn’t good enough. And we could gripe about the infotainment, but that’s better concentrated in the turbodiesel ranks where there isn’t a powertrain of this quality to steal the show. It’ll be a very rare sight in the UK, but if you spot an XE S, know that it’s a damn good bit of kit.