I have a friend in SugarLand Texas ,he is really into Audio and also is in the business of installing commercial and residential audio video equipment.He installed this exact same one and raved about it.I got this for a good price also but now it is really adding up.GM13SR at Best Buy and other places ranges from $129.00 to around $149.00 some places more.He also told me to price shop on Amazon and use that price so Best Buy will honor it.It saved me around $50.00 ,now for the GMOS-LAN-04 again could buy it from $179.00 to $139.00,found one of them on Amazon for like $72.00.
You are correct best to put it back to as close to factory as possible so I elected to get the steering wheel control ASCW which keeps all the wheel controls,the GM13SR for the chimes ,bells and whistles.
I do have the Monsoon Amp and the only thing I will miss is the 6 cd changer in my stock radio.I do hope I get better reception ,I have heard stories also ,one of them is that the radio is matched to the antenna gain so when you change them out you can loose around 20% of the original reception.Again stories,will not know till I get it installed.