+1 to what sgoldste01 said I used the nice big mic that came with the hu. It is mounted right by rear view mirror area. I would say bt call quality is a lot better than oem mic but to each his own
The pioneers have a nav addon that works with these radios however I prefer my nuvi since I travel internationally and update maps quite often
More pics and etc located here
I also had installed the brake override, so that myself and soccer moms can watch movies and look at pics while not paying attention to the road
skipped sirius/xm as I already have my music taken care of.
In terms of bang for your buck
2012 line up
pioneer 4400, 8400(got it for cheap so I opted for this over the 5500 also 5500 did not come in time)
On the 8400 the first batch contained a defective part which made the touchscreen freeze up.
Be careful with the ones you get from amazon if they are from the first batch.
2013 line up
5500, 3500, 8400
navigation addon module