I couldn't sleep at 2am, so wound up poking around this site and researching the Uconnect and Garmin systems and updates. There are many previous posts about updating via the dealer, and the price as $322 by BeerGuy.
It seems the system we have is the 8.4" RB5, and is common with the 2014 Chrysler 300, and SRT Chrysler 300, 2015 Dodge Dart, and the 2014 Charger. The site here will show you each model year:
Uconnect® | Systems | 2014 Chrysler 300 Touch 8.4N/RB5
Selecting Order Map Updates at the bottom at this page:
will open this page:
Chrysler Group | Home | HERE
I used the 2014 Chrysler 300, and it opens the page to enter your 10 digit Unit ID. This you will find on your Mas MTC by selecting, NAV, Settings, System, About. See img_1008. Enter that number and you will go to instructions to purchase and download the 2015 maps for US and Canada. (Sorry, not sure about other countries.) Anyone with other maps, let us know if you can update with your data.
The price is US$149 + possible state tax (mine $10.43) = total 159.43.
Some problems are finding a blank proper sized USB. I tried my iPod and another usb, but the drive has to be blank. So I wound up using a 8GB CF card from my Nikon camera in a multi-slot usb adapter.
Also, the download is not functional on Mac. There is a download link and will download, but the program isn't working. So I had to run the Windows version on Windows, via Parallels. It was problematic, and required multiple resets, but eventually worked. It wouldn't show an internet connection and gave me several of those errors, but finally worked when I just opened a browser page and left it open. Likely not my system, but a poor program. The other option is to just have the usb stick delivered via mail, rather than downloading.
The download took about 3 hours, due partly to my slow connection, and uploaded to the Mas in 45 minutes. I worked in the garage, and just plugged in the battery charger. I'm not too keen on paying $108/hour shop rate for some guy to babysit the reflashing/upload for 45 minutes.
Here is a link to instructions. Once you put your usb in the car, it will upload into the usb the system/map versions and put in a Maserati file. After the download, I looked at the uploaded files (about 4GB), and it had the POI file, Chrysler, and Maserati. So don't think you're getting a lesser product, it they are all the same maps for the same system, but your car tells Garmin what files it needs. If you already have the update, it will give you the message that a 'duplicate file exists', as I recall reading somewhere.
To find your map version (img_1007) you can go to dealer mode. Thanks to hsandhu01 for posting 'MTC "hidden" dealer mode' in these forums.
That's all I can think of. Let me know any questions.
Sorry, photos won't upload. I'll keep trying...