Advent Factory-Style Navigation
I installed the Advent OGM1 factory-style navigation system in my mom's 2008 Buick Lucerne tonight. Alberta just introduced a distracted driving law last month, so she needed bluetooth in her car for her work. We chose this system because it is designed specifically for 2006+ cars and 2007+ trucks from GM. No interface modules or anything like that - it just plugs in. It took me a bit over 2 hours to install... most of that was running the microphone for the bluetooth to just above the rearview mirror and installing the GPS antenna inside the dash so it would be hidden. The car started with cd & xm radio. It now has navigation, bluetooth, cd/dvd, factory xm, onstar still works as it originally did, steering wheel controls still work, it has an iPod connection, and it sounds better than the factory unit.
Overall, my first impression is that this is a pretty good unit. From what I've heard, the navigation part is OK, but not nearly as good as Kenwood or Pioneer units for that. Everything else seems top-notch though, and system and navigation updates are free. The best part is that it interfaces with all of the factory systems and looks a lot like the factory nav unit. If you have a truck with a backup camera, it can show that. If you have rear DVD, it can work with that. I haven't tested it yet, but apparently it is supposed to show on the screen which of the rear parking sensors is detecting an obstacle. It is compatible with Bose and non-Bose systems, and comes with a harness with pre-out connections (front, rear, sub) for if you want to use it with aftermarket amps.
I'll post an update with our experience with it after we've had it for a while and used it a bit.
Here's the before and after pictures: