I have a Brullen muffler on my e30 and nothing is better. Had one on my modded e46 and when I sold it I searched high and low for another brullen exhaust. They were Canadian too out of Markham, too bad they closed up shop around 07 I think. Doesn't help with your choice between Remus and Supersprint as I have no experience with either but thought I'd throw my 2 cents in.
I used to know where a full catback ss brullen system was for a 318 e36. Not sure if they still have it though.