We have an S All4 auto which has recently been having vibration issues in the front end going up hills between 58-63mph. I'm not sure if it's just harmonics of the engine and drivetrain combining to cause a vibration in the front end. You can feel it in the steering as well as the seat.
It only appears when going up hills. I've tried it in sport mode and manually shifting to a lower gear and appears to solve it. I'm taking it to the dealer on Wed. for something else and will have a tech ride with me.

 

Let us know what you find out...very curious to hear. I have as S All4 manual, and am having a similar problem. Starting at about 60mph on any road type, I'm getting vibration in the front end that you can feel through the steering wheel and seats. You can see my hand vibrate on the shifter. I took it in, the mech and I went for a ride and he could feel it too. They looked it over for a few hours (they say) and gave it back to me...told me they couldn't find anything but to bring it back if it gets worse (kind of par for the course at my dealership. At least they didn't scratch the car this time.)

 

My thoughts I relayed to the service advisor was that the trans was shifting prematurely to a higher gear going up hills when it should not have.

Here's the write up from the tech.
Tech road tested and verified the problem. Tech checked suspension for play, exhaust system for problems, any abnormal driveline problems. No problems found. No DME faults found. Tech found bulletin 12-2-11 on transmission hesitation & jerking @ 3k-4k RPM (this wasn't an issue with ours). Tech performed bulletin which required DME software update. Cleared faults, re-test drove and found condition still present. Tech test drove brand new R60 turbo All4 and found same drivability concern indicating normal characteristic of vehicle.
The service advisor took it out after the software update and said it no longer had the issue. Not sure what the tech felt. The advisor said that it changed the shifting so that it would downshift sooner.
I picked the car up last night and noticed that indeed the problem has been resolved.

Update: The problem was resolved for a few days then it reappeared. It happens between 58-63mph as the car is in 4th or 5th gear (automatic btw). I'm going to pursue it to the MINIUSA level. It might be a design flaw.

 

Ok, my wife brought the car back to the shop and I told her to tell the SA to keep the car until they and MINI figured out the issue. It's an apparent design issue and not specific to just our car.
Yesterday the SA called me to ask if the tech could take the car home and perform various load tests per MINIUSA to pinpoint the vibration.
I will keep you all updated. I have a feeling this will bring about a recall for all CMs, at least All4 equipped ones since I didn't notice this issue with our loaner CM non S.

 

The dealer just called to say that they pinpointed the issue to a clutch assembly on the back of the trans that engages and disengages the driveshaft to the rear axle. He said there are a few in the country and will have it in 2 days.
I should know more on Thursday.