Excellent on snow, excellent on wet. Perfect on dry. Good cornering stability. Not so quiet as my previous Goodyear UG7,especially on wet and on some country roads. Good breaking. Still wasn't test it on ice. Became too soft at temperatures over 10 degree C. Perfect at temperatures below 5 degree C.
Enormous traction and grip on snow, excellent stability in 15cm snow (not cleaned road). Even at speed 55 mph. Great tyres.

very very comfort and smooth ride.

Had these Continentals for the past winter. Overall, all the good reviews about them are well founded.
I mostly drove in-town, with weekly country roads, or mountain regions drive. Very good traction in snow, even got out of a frozen snowy muddy 20 cm deep puddle in a forest road, without too much effort. Drove it offroad in that forest about 50km, with places with snow as deep as 40 cm, no problems at all. We had very little snow last year in town, so the traction/brakeing in dry/wet are above my summer Michelin Energy Saver (of course, using the Michelin during summer).
They are just as confortable as the summer Michelins, but not as noisy. Quite quiet these Contis are. In about 6000 miles, the wear on front is about 1.5 mm lower, max, almost no difference on the back. So the wear is pretty good too.

So: Continental WinterContact TS850 is one performant tyre, must buy, with only one drawback - they are expensive. In my country (Romania) I bought them (new) with 385 euros (~300 pounds). And this was the maximum price for a winter tyre on 205/65/r15. Otherwise, one very good all-rounder.

I chose those in december '13 due to a lot of positive feedback from members of the local BMW club. They are very quiet and comfy. The sidewalls feel too soft to me, but this is not a problem as in the winter I don't push the car much.
On snow those provided a superior grip, both on the highway and while climbing a very narrow mountain roads covered with snow and ice. They inspire confidence and really shine on ice, where I think their performance is most impressive.

What I don't like about those is how easily the rears start spinning on wet when taking off. However braking is very good in both dry and wet. I also didn't like the price, but after driving them this last winter, I think that they are totally worth it.

I can not comment on wear since it appears there is none. I have done only a few thousand miles with them and the weather got crazy so i changed to the summer setup. For those few thousand miles there is no visible wear and the tires still look brand new like when I got them from the shop.

I highly recommend them if your winter season is more of snow&ice than wet.

The best winter tire tested in Romania!

The tyres went on about eight weeks ago just before we had snow in the Czech Rep. I previously had Nokian G2's on the car and they did an admiral job until recently when the wear got closer to the legal 4mm and they really deteriorated drastically and made for very precarious driving even with Quattro.
Having heard about how good the new Nokian G3's were, I went to the service centre looking to purchase the them but the owner (also an Audi Quattro) driver recommended I purchase the Continentals instead as he felt they were a better tyre. Upon his advise, I forked out the extra £150.00 and had them put on.
Was it a good investment? Well, In my eyes, they have completely blown away the G2's I had previously.
The tyre feels very sure footed in all conditions and really provides grip in places where there should be none. An example of this is my local high street that had compacted snow and ice on it for some time. An early start meant that the ploughs had not been out yet as I drove through with caution. As another struggled infront of me to get any traction, it felt like I was driving in normal conditions. Amazing.
So, Grip in really testing conditions is a mega thumbs up.
In heavy rain on uneven road surfaces with tram lines and botched repairs, again the Conti's have been amazing, very little signs of aquaplaning and amazing cornering grip.
Heavy snow grip is fantastic, really fills you with confidence. Tested under braking, the car came to a halt in an emergency really very quickly, so much so that I have had to keep an eye in the rear view mirror to make sure I am shunted from behind.
Icy weather is the only weather where the tyre has not been impervious. Sheet ice had the tyre grappling for grip and the traction control going carzy. It is still better than the Nokians. Sheet ice is one surface that no tyre without studs will cope with well so I am not surprised.
No comment on tyre wear since I have only covered 3k miles in them which is just not enough. The tyre fitter said that he got 40k km from his older conti's and expects these to be similar.
The only negative point is the tyre noise which can be heard in the cabin and sounds something similar to a truck tyre roar. It is not intrusive to the point of being a problem but it is there. With the radio on, you won't even notice it.
So in conclusion, this is the by far the best winter tyre I have purchased (and I have been through a few). The only inhibitor is the price even after a hefty discount but what price do you put on the safety of you and your family.
This is an amazing tyre which I will definitely but again and the only word of caution is to watch your speed as these tyres are so good, you'll think that everyone is going slow when infact you are driving like a lune.

The best winter tire tested in Bulgaria

A nice tyre

The best winter tire!

Continental WinterContact TS 850 are really the best winter tyres ever.

bought these as i now do about 30k miles in a year and figured higher milage warranted them. the ibiza has 229lbs/ft Torque and getting the power down in winter is not easy, until i got these fitted. with summer tyres i could see TCS light on up to 50mph when agressively accelerating, no TCS with these on the front. My fuel economy was about 5mpg better over the summer tyres. (this is probably in part due to the winter tyres being 185/55 R15 versus summers being 205/50/R16) I had them on for 10k, hoping to get another 10K this winter with the same pair.

I've just had 4 of these fitted today (my first ever winters), 2 August 2013 in 25-30C temperatures! I would have liked to have got another couple of months out my old tyres, but safety comes first. My intention is to run these tyres all year. First impressions are very good: tyre noise seems more subdued, ride comfort better and all other parameters similar or superior to my old premium summers. I'm looking forward to seeing how the tyres fare over the next few months (hopefully years) and what sort of mileage I'll ultimately get out of them. I read (by Continental I believe so maybe an element of bias) that these TS850s will not wear any faster in the summer months than true summer tyres. I intend to monitor wear (I usually switch front to rears half way through the tyres life) so will report back.