I've seen part numbers listed by both Luk and Sachs, the Luk usually being cheaper but I don't think it's the right size (220mm as compared to the 228mm)? Isn't the flywheel 228mm? Just wondering since I'm taking mine to a machine shop to get their verdict on whether or not I should replace it, I'm thinking yes due to many radial cracks along the outside of the contact surface ring. If there are any other DMFs that I should be researching please let me know, as of now I think I'm going to get the Sachs.

 

Now I don't have a perfect memory, but it seems to me I read on here somewhere that the flywheel was a one and done part. Swap it out with the clutch, pressure plate, and throwout bearing. All together.
hop over to the drivetrain board and do a search. Lots of good info there.

 

You can machine a solid flywheel....
Dual mass from all i have heard can only roughned up a bit with a scotchbrite pad if you want to reuse it...
Most oem parts have 2 scource....so to hear both are oem would not be surprising...
just get the right one.

 

The OEM dual mass flywheels are 228mm for the R56S. The current manufacturer is GAT.