Anyway, Blitzsafe recently updated the adapter to accomodate XM. I was actually over at their facility a couple of weeks ago and we were doing some fine tuning and testing of the new adapter.
They had some issues with some other cars but the Accord's adapter works pretty good.
I currently have their latest version of the adapter installed in my car. It works really well. I have my DVD player and amateur radio equipment running through it.
No more FM modulator, woohoo!
And no, it isn't just cobbled together from any old parts. They have their own manufacturing facility where they make and assemble the stuff. So it's not like some DIY electronics project.
And no, it's not just parts you can buy off the shelf. The main part of it is a microcontroller with their custom software. You can't copy the software either, it's copy protected.
But at $99 it's not bad. I got mine free, of course but at $99 to get an aux input or iPod interface it's not a bad deal. They have no plans for steering wheel control (they claim it's not necessary), so if you want that either get the Honda unit ($400) or dension iceLink and give up your XM.
The issues with audio bleeding, the unit locking up etc have all been solved for the Accord. There is zero ignition noise but I do suspect that it has an RFI ingress problem (but it's not like you guys are running a high powered radio transmitter from your car like I am).