New to BMW. Purchased a 2018 540ix Sport in October'17. It's a daily commuter for me (120 miles round trip - mostly highway) and I now have 36K on 18 inch Hankook Ventus S1 Noble RF. At 10k miles, I noticed cupping on the outside front tires with less so on the back tires. At 15k miles, I had the dealer rotate front to back. It worked for a while and then at 30k front tires, originally on the back, were cupping. Rotated again to try and get a few more miles out of the OEM tires. Probably could get 45K on these tires, but they're extremely noisy (at 30k+) and driving me crazy. I plan to keep the car for a while. Any recommendations for replacement tires? Should I buy at the dealership or at a tire warehouse? Dealer recommended Continental RF or the OE Hankook. I live in New England. Noise level and tread life important considerations.