Im going with the Hartge Diffuser as i like the fins in between the tips.
Ive got the trunk floor and now waiting for DP's to arrive so that we can do the whole turbo back exhaust at once. Will most likely be first week of the new year.
It will be very similiar in design to the Akrapovic Evo exhaust for the 1M (two tips muffled, two unmuffled), hopefully I can get the same sound as the Akrapovic