Well, I tried the Dension Ice-link Plus. I am sad to say that it doesn't work. I am awaiting for more info from their support team to test out other scenarios.
The main issue is that since our RAV4's now have the Aux input, there is no way to select the Dension(or any other ipod adapter) as a CD changer. The connectors are all there in the back of the head unit but I believe its now its being used as the link to the optional rear entertainment unit.
Update: The head unit sees the dension ice link but can't communicate with it. Maybe the sound gate will be better since it can change from CD-changer to md changer modes.
On the positive side, its pretty easy to remove the radio unit. Just make sure you use some towels to protect the surfaces. I will post instructions in another thread.
I have the JBL unit but I think it works the same with the non-jbl units.