I had a huge weekend of driving pending (son's basketball tournament) so I caved in to my need for safer music and mobile calls and bought the Belkin AirCast Auto. For now it was one of a few choices as my iPhone has a munted audio jack.
The local Officeworks matched the $89 retail price at Dick Smith, JB etc, but this adapter is even more affordable elsewhere and online.
My car already has the aux-in /12V in the cubby.
I ran the cable out of the cubby, down past the seat belt anchor and under the center console trim, out of the handbrake boot, around the gearshift boot trim and placed the mount just in front, to the upper right of the gearshift beneath the HU... right where it's in reach, but obscured by my knee (when my foot is off the clutch). Not that the flashing blue ring is very visible anyway (for call notificaction when not using aux-in). Thus I recommend not using the sticky mount till you are sure you're happy with the placement!!!
I was prepared to be mildly disappointed (low expectations), but I'm actually totally stoked!
My music (podcasts and playlists on iPhone4), sound great via the Belkin, aux-in and McIntosh 6 CD.
As long as you have some music queued/paused on the iPhone, BT activated/paired, your music will play as soon as you press the Belkin button after the car is started. And it will pause when you take a call or turn off the car. Sick!
Of course it helps to have your playlists sorted, in addition to Genius, DJ, etc I have some smart playlists e.g. "mixes" (anything longer than 10min).
When receiving a call whilst using aux-in to listen to music, which is most of the time for me, the music is paused and the ring tone is heard through the car speakers and a single push on the Belkin's button answers the call. No complaints from people calling me either, and BT handsfree to BT handsfree calls (another dad in a new Volvo

) were fine). I even managed to get the timing sussed for two-push track skipping (one thousand-one timing works for me). That's all I require for now, but I'll get around to checking out any other of it's features later.
In summary: I'm impressed, I can definitely recommend this item, and as the Anycar Link or Parrot BT units offer increased functionality and even better integration, then I'd have to say that there are definitely great options out there for "iphone connection for calls and music" with some Subaru head units and I'll definitely consider upgrading in the future.