For the first six months that I owned this car, the most irritating feature was the second to first downshift. accelerating from (for example) a rolling stop in second would convince the gearbox that it had to downshift... NOW! With a predictably large THUNK as the torque of the V8 mashed the cogs together. There was no need for this kind of behaviour, the engine has more than enough torque to pull away in second.
I complained regularly about this to the dealer, as it was enough to put me off the car completely. Driving through town from light to light was an exercise in caution as I accelerated away. The problem was unpredictable and made my skin crawl at the way it tortured the gearbox.
Then after six months the dealer came up with a new shift pattern program for the gearbox. The problem went away and has hardly been seen since. Very occasionally after a high speed run, up to a light the THUNK will return, but it has only happened a handful of times since the reprogramming.
If you have an S-Type R, RUN, don't walk to your dealership, and make sure that you get this done. It transforms the car and I have been as happy as a clam ever since.
Mechanically I have had very few other problems with the car. But here are a few:
Sometimes the door locks get "confused" and will not open and close from the master unlock/lock switch on the center console (by the way, why is it there Jaguar? Every car with any sense at all puts that switch on the driver's door).
When it is cold outside (a few degrees below freezing) and I fill the tank with gas, this can cause the fuel computer to go on the blink, the gauge reads zero and the LED computer gives an error... until mysteriously it comes right back up again. It always comes back after a few minutes, so this is simply an electronic quirk and easily lived with.
This car is seriously fast, with nearly 400 hp on tap (even allowing for a little Jaguar overstatement). It is also relatively compact, quite heavy, and extremely torquey at low rpm. All this is combined with the famous Jaguar "hush", it is very quiet inside the cabin, which makes for an interesting combination of sensations.
The weight and the relative quiet means that you can "squirt" from 70 to 120 mph with no effort or fuss whatsoever. You really need the speedo to know how fast you are going. The engine has a deep note through the big twin pipes, and the supercharger gives only a subdued whine that can be completely overlooked by the "normally aspirated" Jaguar fans who might be vaguely discomfited by the tradition-breaking belt-driven pressurization. I live at nearly 6000 feet in the Rocky Mountains and I will take all the boost that they can give me. The power curve is relatively flat and the engine doesn't even appear to be working at all until over 4000 rpm, at which point you have probably left double digit speeds well behind. The mapping of the engine control computers almost never lets you wind the engine up above 4500 rpm.
The six speed automatic box is immensely over-geared, which means that 85 mph shows at 2100 rpm in sixth, and in the same gear you can peg the speedometer at 160 mph at a shade over 4000 rpm. I don't know how fast this car is because the speedo really needs an extra 30 mph on the dial. If this car is really limited to 155 mph electronically as is rumoured, then mine has either been turned off... and I wasn't the one that did it... or the speedo is fibbing by a lot.
For the faint of heart in these politically correct times, this particular speed experiment was carried out on a dead straight, flat, 8 mile stretch of Wyoming asphalt that was occupied only by two living things. Myself, and a lonely looking antelope way off in the distance. Not exactly a "private race track" but very close. In addition the brakes are sensational and really inspire confidence, I think that they are 12 or 13 inch Brembo disks all round, and they pull the car to a halt with real authority.
The greatest feature of this car... there is virtually no "gas-guzzler" penalty for all that power. At a steady average cruise of 85+ mph, you will get anywhere from 23 to 26 mpg (and that "g" is the "short" US gallon). The car is thirsty around town when average speeds dip to 20 mph and below and it will give you only 14 mpg (but my 1993 3.2 V6 Taurus SHO did almost exactly the same mileage in town), but at high speed it is a marvel of efficiency. This is almost entirely due to the 6 speed ZF gearbox which allows the engine to run at phenomenally low rpm with the supercharger delivering minimum boost. This combination at times can be a little surreal as many of the usual laws of physics can appear to have been momentarily suspended. To get a feeling for what I am talking about all you have to do is find a "steep" hill and accelerate straight up it.
The electronically controlled "anti-slip" feature can be a necessity as it does not pay to accelerate while turning even moderately hard. I have done this just once (once is enough), and the electronic DCS system stopped me from pulling a completely unintentional rubber burning doughnut in the middle of an intersection. The power is best applied in a straight line, or in a smooth curve. Don't try and pull a U-turn with gas. The computers will save your hide, but if you are smart, you will learn to feather the accelerator gently while manoeuvring.
The handling matches the rest of the car. It is capable and has never given me any cause for concern. You can drive your aged aunt around town and she comments on how quiet and smooth the ride is. Drop her off and throw it into the turns with some verve and the computer controlled suspension flawlessly adapts.
One disappointment with this engine? Open the hood and there is almost nothing to be seen. Due to all the heat channelling shrouding and plastic trim, it is as black under the hood as a Mercedes engine bay. Somewhere in there is a supercharger and twin water/air intercoolers, but only the very tip of the supercharger belt pulley sticks out coyly from underneath the covers.
This car has been well designed by Jaguar, and for the mission it was engineered for, it is almost perfect. In my opinion Ford has done a great job with Jag, as the partnership has been an evolutionary one... the resulting hybrid has turned out far-stronger than the original thoroughbred. Some people think that the "R" supercharged version is too much four-wheeled testosterone, and that the regular 4.2 V8 is enough. I have owned and driven both, and they are wrong. Around town the R needs to be treated with respect, but that's as true with a 454 powered pick-up truck as it is with the Jaguar. It is on the open highway that this car really shines, and that's where the supercharger comes into it's own.
It is a looker with a retro flavour, if you are old enough to remember the old Mk II's, and the styling always draws comments. But at the same time it is low-key. It slips in almost unnoticed amongst the gold trimmed Lexus'es. But even people who are not car buffs recognise it immediately as a Jaguar. That is not something that the Infinity/Lexus/Acu-whatever crowd can necessarily boast.
In conclusion, the performance, both accelerating and braking, is completely out of proportion to the looks. For someone who really likes driving, this is an ideal combination that takes the best advantage of our beautifully engineered, but heavily policed and speed limited public highways.