You looking more for comfort or performance?
I have the Cooper RS3-A on my CTS...
They are an all season performance tire. Works great so far in the rain and dry. Handles well and has a 500 treadwear so not full Touring tire but also not a super high performance tire.
If you want longer life then look at touring tires like the General AltiMAX RT43.
700 Treadwear so should last longer and give a softer ride.