Since mine is a middle east spec, i had to replace the radio unit and the infiniti control center buttons but that won't be applicable to all of you in the U.S. hence I will attempt an explanation of the install and the device
This is the back of the radio (It looks exactly the same as my old radio but i wasn't sure if the mediabridge would work so i swapped it out anyway). The two connectors that are important are the sat connector and the vehicle harness as highlighted in the picture above. There are three plugs that come out from the mediabridge, the first connects into the vehicle harness, the second into the sat connector and the vehicle harness that was originally plugged into the radio will go into the third. The original sat connector that went into the radio will stay disconnected. All other harnesses that i haven't highlighted will stay plugged in as normal.
The Audiovox mediabridge allows you to retain satellite radio but you need to buy an additional part for that
the above dipswitches need to be adjusted to retain sat radio but since i never had sat radio and couldn't care less for it, they are both in the off position. The manual explains which to keep on to retain sat radio with the additional module.
I've routed the device to the center console as below. I disconnected the charging port and passed the wires through the existing hole.
Below are the ports on the device.
I passed the USB to the cup holder. It is currently connected to my iphone 6+ and allows me full contol via the radio buttons but i intend on using a flash drive since i don't like sorting through music on the phone while driving.
Mic is routed to the driver side A pillar. AUX, USB and bluetooth all work well. The volume is really loud with the volume turned up half way. People i have talked to over bluetooth or with my phone connected via USB can't tell that i'm not talking via the handset. All in all i'm really happy with the purchase. If someone wants USB or sat radio, then this is definitely a better option than the USASPEC since it doens't have either of those functions. I will do a video in the near future.