SLK/R170: Stereo question

I'm the proud new owner of a 2004 SLK 320, and among the first things I want to address is the stereo/phone situation. The car has the OEM stereo with the CD changer in the trunk and the voice control lever on the steering column. I don't care for the changer being in the trunk, nor for the lack of XM/Sirius capability, so I'd like to upgrade the radio. By the same token, I'd like to be able to use Bluetooth to take phone calls over the radio, which most new stereos (Kenwood, JVC, etc) can do. However, I'm quite intrigued by the voice control lever on the steering column and wouldn't mind being able to make use of that as well.
What are my options both in terms of potentially going with something newer from a Mercedes dealer (radio that supports Bluetooth and satellite radio), or is there any way to make use of that lever with a 3rd party radio?
Thanks in advance, and looking forward to becoming a member of the community!
It works ok with my iPhone 4 and is about 95% accurate in voice commands when stationary (but 30-40% with road noise) and mediocre in clarity on calls incoming / outgoing.



