New Continental Contisportextreme 225/45/18 (22 lbs each!)
18x8 +48 Rota Tarmac 3 (20 lbs each)
My 17s weighed close to 22 lbs and the tires were 26 lbs each, so even though the Rotas are not the lighest wheels around, I still reduced the unsprung weight by nearly 24 lbs over my previous setup.