I found some time to swap on the 400m wheels and Continental ContriProContact SSR tires. I could've waited another 1-2 months, but I was curious to see how the car would perform differently with a square setup and all season tires compared to the 441m staggered setup with summer tires.
While I had the wheel and tire sets off the car, I weighed them on a bathroom scale I keep in the garage. Not super accurate, but it gave me decent ballpark weights.
The 400m wheels (18x8) with 225/45/18 Continental ContriProContact SSR run flat tires weigh 53 lbs each.
The 441m front wheels (18x8) with 225/45/18 Bridgestone Potenza S001 run flats weigh 50 lbs each.
The 441m rear wheels (18x8.5) with 255/40/18 Bridgestone Potenza S001 run flats weigh 56 lbs each.
So overall, the weight of my 400m wheels/tires is the same as my 441m wheels/tires.
Here's a crappy cell phone shot. I'll take better photos eventually.