I dont have the SM3s, but I did end up buying custom rims that are 16X7s. I have lowered the rear, and 205/45/16s work. Even with the lowering job there is travel space so the tires do not hit the wells. I added a 15mm spacer so my car sits a little staggered and also wider in the back (the outside wheel line sits right outside the well)
The S drives are nice, but if you dont want that bumpy of a ride, select a bigger wheel size. It will change the gas mileage and will feel a little slower off the line. I went with Kumho Ecstas because I wasnt going to fork out another 100+ per tire when I could get them all under $200. My tire noise isn't too bad, but I havent rode in a smart that has the SDrives in them.
Also rotation becomes a non factor because you can do a normal tire rotation every 5k if you want. I will do mine at 10k.