For thos3e who asked about the GM sub, do yourself a huge favor and check out Steve at ********s (
www.********.com) setups. You will get a LOT better equipment for a lot less money.
If your car has bluetooth (2LT and 2SS standard) then you can stream music. I didn't realize that the convenience and connectivity option added to a 1LT or 1SS also added the bluetooth connectivity. If that is the case, and you want bluetooth, you must get it on the car as built by GM or prepare to beg your dealer and onstar too allow you to add it later...many are failing so you have been warned.
I actually like the Boston System with the addition of a 12" sub, 500w mono amp, and the ******** x3 wiring harness. I run mine with a remote sub volume control knob hidden under the dash to fine tune the thump added. It adds just enough bass that it balances nicely with the tweeters in the BA speakers. You can then turn the bass down on the head unit and not overpower the BA speakers and get a well rounded sounding setup. Yes I have had better systems that were all aftermarket but for a stock system this one really isn't that bad. Also the BA system having an external amp allows you to use the ******** wiring harness(s) and build onto the system. Without it and you are back to wire splicing, replacing all speakers, etc.