Well after a lot of time spent researching I decided ± $800 (parts only) just to have questionable bluetooth functionality, was too much and after a lot of digging around settled on the Motorola TK30 aftermarket kit as I found it for about $80 on amazon and then went about finding an interface kit for it. At first I thought you needed a MOST fiberoptic unit and harness. But I was advised by JustCarKits in the UK that only wiring was needed and they have kits for 2005-09 LR3's with and without HK 9 speaker stereo heads. I had it shipped to the US for about the same amount as the Bluetooth unit and after a lot of worrying pulled the dash apart and installed it.
I mounted the interface on the little well on top of the center console just to the right of the NAV screen with only a 3/16" notch in the forward edge of the console plastic. the install was not too bad, the hardest part was figuring out where to put all the additional wiring. In the end I was able to velcro mount the bluetooth unit on the underside of the NAV tray just on top of the radio head unit and distribute the wires down each of the vertical voids in the dash frame either side of the head unit with the major part of the harness up into the dash behind the NAV unit. Naturally that meant I had to take all the console units out, Head unit, Hazards unit, Climate control unit, as well as the NAV but that wasn't so bad.
It's not as pleasing as seeing nothing (like the dealer system) but it is way more functional, with support for two phones, bluetooth music, iPod/iPhone connector/charger, usb port for thumb drive music and auxiliary port for a Garmin NAV or an mp3 player.
It was quite frustrating at first because it only worked intermittently until, after talking with Philip Henderson at JustCarKits (incredibly helpful), I upgraded the software from Motorola's site and then it became way more stable.
It still has brain f_rts and gets confused occasionally, but I discovered that pressing and holding the top and bottom buttons simultaneously, forces a reset and 9 times out of ten that cleans up the connections without having top turn off the ignition or re-pair the bluetooth.
It took a little while to get used to the interface which is a two line LED display with a spinning knob for scrolling surrounded by four "buttons" which change function (and Color) depending on the device used. For $160 and a day to install it (I took my time) it is a wonderful solution.
The head unit mutes and displays "Phone" whenever the TK30 takes over control and when it's finished it returns to whatever was playing. It uses the AUX channel on the head unit for Music from the iPhone/iPod, whether through bluetooth or the connector.
It has voice command capability as well as voice command pass-thru to the iPhone so if you phone is in your pocket you can press a button on the TK30 and it connects with SIRI on the iPhone and lets you do what the iPhone can do.
The sound quality is REALLY good, especially compared to a headphone jack into the socket at the back of the console. No more buzzing or ticking interference. The only downside is that the sound coming from the iPhone/iPod for anything other than the phone, which has it's own volume setting, is too quiet. You need to pump the head unit to above about 27 to hear music well. That's ok, it can handle it, but you need to remember to turn it down if switching back to radio or CD player or you will deafen yourself or possibly damage the speakers.
The Steering wheel volume controls still work for everything and the mode button allows switching between audio inputs (Tip - Hold down the mode button 5 seconds for AUX).
I have used it with iPhone3 as an iPod, iPhone 4s as iPhone/iPod, and mostly iPhone 5. it all works well except for iPhone 5 as an iPod, but I am convinced it's because of the necessary lightening adaptor. It doesn't seem to like it. So I only connect the 5 via bluetooth for Phone and for music. I think a replacement cable with a lightening connector would solve that, but it would probably need to come from motorola. Otherwise, It's great!
As far as charging the iPhone it does fine except again with the lightening adaptor it seems to be a trickle charge not enough to keep up or exceed the charge needed if you are playing music on the iPhone as well as using google or apple maps through bluetooth. So keep an extra lightening cable and adaptor in the car for an emergency quick charge.
BTW, This interface wiring kit from justcarkits also works on the Parrot bluetooth units, but I have no experience with those and they cost at least twice as much. I would be interested to know if they work any better with the iPhone 5 lightening adaptors or if they have the same iPhone music volume issue.
I am very happy with this solution, but then after 9 years of no bluetooth in my LR3, maybe I'm easily pleased