I just finished installing the bmw oem sirius kit on my M coupe
Installation was fairly simple and if you have done a DICE installation its pretty much the same thing.
took about 30 mins total
Powered it up, everything works well, even the dice works flawlessly.
On my drive up this morning I was having signal issues, I expected this however.
I mounted the antenna under the roof of the car. Reception was good in open areas but horrid in between mountains.
To all coupe owners..where did you mount your antenna? Im am trying to avoid external mounting.