Hey Everyone!

First post so please go easy on me Hopefully I'm putting this in a logical place...

Just bought a B7 2006 Audi A4 Quattro Avant a few weeks ago, and am loving the car so far! I'm interested in being able to connect both my iPod and my android phone to my car to play music.

Currently I have the Symphony 2 head unit with the 6-disc in dash CD changer with XM Satellite radio. I also have the stock (I think) bluetooth interface that allows me to make/receive calls through the stereo. All that stuff seems to be working

Currently I'm connecting the iPod through an FM transmitter, but the quality isn't fantastic, and I don't want to have to keep switching connectors all the time if I want to switch between the two devices, though I suppose the iPod could go away if I can connect my android phone to the stereo reliably. The main gain I'm looking for is to be able to control volume/song/etc from the head unit and steering wheel controls.

I've been doing some digging, and I've found a few options (I think):
Dension Gateway Lite BT - GBL3xxx: http://www.dension.com/product/gateway-lite-bt-gbl3xxx
Dension Gateway Pro BT: http://www.dension.com/product/gateway-pro-bt
or
GROM-USB2P-AUD: http://gromaudio.com/store/usb_adapters/audi_98-10_usb_bluetooth_android_ipod_adapter_digital_inte rface.html
(sorry no links, apparently can't do that until I've got 5 posts)

The latter is a bit more expensive with you add in the bluetooth and wiring harness options. My theory is I can have a micro USB charger connected to the phone and then use bluetooth to connect and play music, while having a cable for the iPod connected somewhere if I want to use that option.

Now to the questions (thanks for reading this far down already!):
- Are there any other methods/adapters out there I should be considering?
- Does anyone have any experience with any of the above adapters? Is one better than the others? Does it work well?
- If I connect my phone via bluetooth, is that going to cause a problem with the existing bluetooth interface? Is this an either/or scenario? Or does the bluetooth offered in the adapter duplicate what I already have?
- Will I have to disable any functionality on my stereo in order to connect one of these adapters? I suspect I might lose the XM radio, which I'm OK with I suppose since I only found out I had it last night . Although I've read that there was a factory option to connect another CD changer to this head unit, in which case there might be an available connector on the head unit?
- Are there any other parts I'd need to get to make this thing work?