You know that fffeeling you gget when you dddrink to much CCCoke? All jjjumpy and jjjittery? Ready to gggo at a mmmoment’s notice? Feet tttapping, legs vvvibrating? Not sssure which dddirection you’re headed, bbbut sssure you’re gggoing to ggget there as fffast as you cccan?

That’s what it’s like driving the Mini Cooper S

The supercharger is there all the time. Off throttle. On throttle. High revs. Low revs. It’s there like a shadow. You can’t go anywhere without it. Which is a good thing considering that it allows you to carry a higher gear lower in the rev range than you would dare with the normally aspirated Mini – at least if you want to accelerate with anything approaching aplomb. It’s slight whine never intrudes, but reassures that 163-hp is not far away.

The supercharger sits beneath an intercooler mounted atop the engine, and fed by a large scoop (a.k.a. the “S-hole”) near the leading edge of the hood. It feeds power to a six-speed Getrag manual gearbox that is slightly firmer, but no less accurate than the exemplary five-speed on the non-supercharged Cooper. (Oh what Cooper owners like me wouldn’t give for another gear that would bring revs down at highway speeds.) The power is 48 more horsepower than the Cooper can muster, which gives the S enough grunt to travel from 0-60 mph in 6.9 seconds, fully 1.6 seconds faster than the Cooper.

I never had the chance to put a stopwatch to it, but I’d swear the Cooper S is faster than that. Maybe it’s because the power is available from just off idle, whereas the Cooper has to reach 4,000 rpm before things get frenetic. Maybe it’s the supercharger’s growling whine under hard acceleration, or the engine’s lack of peakiness. Maybe it’s just darned fast for such a little box, something you don’t fully appreciate unless you find a deserted area suitable for an all-out acceleration run. There you’ll discover that nothing beats a small car with lots of power.

As day-to-day transport, the Cooper S isn’t perfect. With the optional 205/45-17 Pirelli euphori@ (read: “euphoria”) performance tires, the S can get a bit jittery and jumpy. On smooth roads, it isn’t a problem. On rough roads, the ride motions become very sharp, and cause the passengers to bounce along with the car over the road imperfections. I’d almost bet the springs and dampers are identical whether you get the 16-in. or 17-in. wheels, but the lower, stiffer sidewall on the larger tires increases the effective spring – and damper – rate. Softening the ride through a greater range of damper valving and a slight reduction in spring rate might anger the sport compact crowd, but it would not only make the S more comfortable, it would improve road holding in less-than-smooth turns.

The real question comes in whether the 48 horsepower difference is worth the $3,000 premium. If I was autocrossing or racing a Mini, or wanting to thoroughly embarrass a larger, more powerful car, I’d opt for the Cooper S. The low-end grunt and always-there horsepower are worth the price. And I could get used to making sure the everything was stored correctly, and the rear seatback latched firmly in place in order keeps the rattles to a minimum. Where it would be a problem is in day-to-day transport. Not only for the slightly rougher ride, but the constant temptation to dip into the throttle just a bit more. The drive to work would shift from one of keeping the momentum up, to one of squirting from hole to hole in traffic; a very easy thing to do in the Cooper S since you have the power on hand to close almost any gap, and the size to fit where most others can’t. Better to spend the $3,000 on optional equipment, I say. Otherwise the greatest number of trips will be back-and-forth to church for confession.