[ctuna]

You can have side effects .
Did you read the part about repairs and software updates.
You need to do a parallel mount of the old system or be
ready to put your old head unit back in if you need to go
back to the dealer for anything.
The connects 2 Harness is what a lot of people are using for this
now.
Also you need to know which of the three BMW systems you have
to do a good job and wire it correctly.
You need to identify your BMW system what year car do you have?
If its US 09 or earlier it will be Hi Fi or Logic 7 system if its 2010 or early 2011 you may have stereo or base system .
There will still be issues with things like SOS and PDC if you have it
no matter what system you have.
The basic thing is to do it correctly its more than just throwing a harness on a Head Unit in and some steering wheel controls.
The member BMW325i has done this and knows how it goes.
Best to list the year of your car and what options it has to get
accurate help.(which system and which options)
Don't throw your old BMW head unit away of sell it you may need
it to get work done on the car.