I've read through the whole other thread in the audio forum about the integration kit
After 27 pages and reading the actual users manual that comes with the OEM kit this is what I've concluded.
It CANNOT be used in parallel with XM, it's either or. This is stated implicitly in the manual.
It was created for pre 5v iProducts (i.e. iPhone 3Gs, 4 iPod Touch and new gen iPods) the old iProducts used 12v for charging, the new use 5v. There was a change to the pinout so the OEM kit will not charge the newer products if they have updated OS because it recognizes the different pinout. Apparently you can get a passthrough from Scosche that address this.
As for integration, it should work just fine. You may get the "not supported" message but cancelling it should still work. Many people seem to be using them fine.
The newer kits say they work with iPhones, so I am guessing the pinout was updated on those. I would hope a product sold in 2011 would work for a phone purchased in 2009
Myself, I bought a cable a few months back that hooks to my iphone and has two output cables.
One is a usb cable for chargin, the other is a 3.5mm aux plug for audio. So I can now hook my phone up to ONE cable and get charging and audio. I did need to buy a usb adapter plug for my power port, but that will come in handy for other devices too. I have since come along some cords that have the plug built in for a cig outlet.
My only negative is that it doesn't charge the phone as quickly as a regular charger, but I think that's because I bought a 2 usb adapter and it's not outputting enough amps. I think I'm gonna pickup another single usb adapter and see if that changes anything.
However the setup now does not drain the battery when listening, it at the very least maintains a charge.