I've installed xcarlink last weekend! It took me about 3.5 hours (I take my time
) but I've got that done myself and I think it was well done. A couple of issues I've found that I haven't seen documented in other posts that may be useful to others: my Civic has the factory/dealer fitted Honda Bluetooth but it doesn't connect to the Aux port, which was unused, but I've bought a Y cable just in case, so I've decided to use it leaving one of the two connectors free. When I've connected xcarlink to the Y cable for testing it, my radio couldn't find it! As soon as I've connected xcarlink directly to the Aux port without using the Y cable it worked fine. Not sure whether I've got a defective Y cable or you need to have all three ends connected to get it work. Ideas?
The next issue is a side effect of this: after taking all apart, I was thinking of installing xcarlink in the armrest storage, so I've routed the cable for that and I've realised it was too short, with the device barely reaching the back of the handbrake! That makes sense as the excellent how to was based on having the Y cable, which provides some 20cm extra length. So if you buy the USB-SD-IPOD "all in one" model, bear that in mind.
So in the end I've had to install xcarlink inside the little storage area below the radio, as per original idea. The only problem with that is that unless you have tiny USB sticks, the little door will not close completely when the stick is inserted, so to have a cleaner thing I've switched to SD cards for my music, and that fits perfectly and I can keep the little door shut all the time. Also, if you want to connect an iPod, the connector for that is on the back of the unit with an extra cable so I need to pull the unit forward to use it that way. It works because I've left some loose cable length at the back so I can pull it out and push it back inside. The little storage area may not be big enough to accomodate xcarlink, the iPod cable and the iPod itself.
Sound: to me it sounds as good as the factory CD player, no noise anywhere and I'm pleased with that. The display just shows "CDC x-track y" and I can use the CD+/- keys on the radio and the Track+/- commands to navigate, better than nothing. I still need to figure out the best way to organise my music on the SD card. The information on the xcarlink website is out of date and you don't need to name your folders CD01, CD02 etc. Mine just works with the original names but doesn't seem to read ALL the folders: I think it can read 15 but not sure where is the limitation, so I'll try email them for info.
Thanks to all the guys who posted good info on this and the excellent how to!