I purchased a new 2016 S7 with the 20 inch tire option. Love the car, not so much the tires. Tires are Pirelli P Zero 265/35R20 Summer Performance. I was reading the Pirelli information about the P Zero line and they state that they do not recommend using these tires when the temperature is below 45 degrees F. Also, I was driving in rain the other day and I felt the car start to hydroplane. So, I want to replace the tires with an all weather tire and I might like to go to a 19 inch tire / wheel combination. I don't really care about the extra performance that the P Zero tires might give me because in this country we have speed limits instead of the autobahn.

Any suggestions on tire / wheel recommendations and the issues involved with going to a smaller wheel size on the S7 would be appreciated.