If budget is not an issue and safety is top priority I have one word, three letters and one number:

Michelin MXV4

Interestingly though I see this tire was bumped from its number 1 spot on Tirerack. Speaking from first hand experience nothing delivers a more quiet ride, and superb traction across all road conditions. If you are in deep snow area these will never approach the performance if snow tires. They are great on my s60 and were OEM when the car was new, I see why. Does not perform like a true performance street tire but crushes all other areas. All four mounted balanced on my stock 16 inch S60 rims was about $900 at Sears, they had a rebate when you bought all 4.

In years past I've had:

Yokohama Avids - good value tire, was always happy
Goodyear - yeah got a good year out of them and thats it
BFGoodrich - would not purchase again


Just my two cents.