I have looked and looked and looked some more but I am unable to find a stubby antenna that will work with my navi. I have a 2009 Cooper S R56 w. nav. Could anyone out there point me in the right direction.

 

Whatever "Stubby" should have no effect on your Nav (or Sirius Radio)
as the Satellite Antennas are located within the Base of your Antenna Installation.

There may well be a noticable difference for your AM/FM and HD Radio reception
of the more distant stations and this would be the factor to consider for your choice of stubby.

 

^
exactly

any stubby w/ a 6mm thread will work.

 

Why do some sites say not compatible with nac equipped. Look at Minimania.com for example... none of there antennas "fit" my car according to their information.

 

I've run my MCCS with Nav and HD without any antenna and they both worked fine.

 

No problems with the Craven Speed Stubby and the NAV on my 2007 MCS. Can't see why there would be a problem with any other brand because the NAV doesn't use it. Not sure what MiniMania is thinking.