I know this is an older thread but, thought I'd add my experience:
I got the 430n RHB unit in my 2012 Rubi with the connectivity group and have been playing with this system for about a week and a half...
The Uconnect system is pretty solid. I have a Samsung Vibrant running Android 2.3.5 and all the features work when synced w/Bluetooth; Phone book access and audio streaming, with both steering wheel controls and voice commands working. The audio quality of the mic on the other end of the call is great and the speech recognition is pretty spot on. My wife has an HTC Espresso (MyTouch 3G Slide) that runs the same version of Android and, while everything works with it as well, there is one exception in that the steering wheel controls don't seem to allow control of track playback from the phone. You can sync 7 devices to this unit. This is pretty handy for me. I usually get tasked with hauling everyone to the studio so I'll be able to sync all my bandmates' phones and dole out control of the music wirelessly.
The Sirius functionality is pretty killer. Especially the Travel Link. My wife had Sirius for a year when she bought her Edge. We enjoyed it at first, but the novelty quickly wore off. I mostly prefer to listen to my own tunes, on my terms. Not sure I'll subscribe at the end of my year.
The interface is pretty responsive. It's not the best laid out but, it gets the job done. Streaming audio from a Bluetooth device was the only time I experienced lag but, that's to be expected. The 6-speakers and sub sound great. The balance/fader control is a square area representing the interior, split into quadrants where you touch the screen to position a block in your desired position. It has a 3-band EQ too. The sub has plenty of punch/boom to suit your preferences.
The internal hard drive is fairly spacious. It lists 28 GB of available space for your own tunes. This is almost a perfect amount of space to keep you entertained for quite a long time. You can also transfer pictures to the unit. However, you are only allowed to have 23 pictures (24 total but, one slot is taken up by the default image it ships with). Furthermore, the resolution of the screen is so low that you have to crop your pics to a fairly pathetic 240x158 pixels. All images take on a soft, somewhat blurry appearance. It also won't slideshow the images. You have to pick one as the default display and even then, you have to close all open tabs to ever see it.
Transfer/organization of music is really the biggest negative about this unit. I have transferred music via a thumb drive attached to the front USB port, a data DVD holding MP3s and through a phone and media player with the "connectivity" USB port in my center console. They are all SLOW as hell, with the DVD method being the fastest of the three. It takes me about 15 minutes to drive to work. It can transfer 7-10% of 4 GB thumb drive during that time. Fortunately, it will resume each time you start the vehicle. Otherwise, you'd have to sit there for 2 1/2 hours or take a long road trip.
My music library on my home server is made up of MP3s and clocks in at about 120 GB and growing. I organize my tunes by Artist folder, with sub-folders for albums. I have painstakingly entered all ID3 tag information, including album art, into each track. Unfortunately, the MyGig can only read 1 folder deep so, when I transfer the stuff, it throws all the album folders into the root of the hard drive together. Browsing by folder doesn't seem to be an ideal option at this point. It will create a playlist for each folder though. If you've tagged the files properly, the best way to search is by artist. When you select an artist, it will throw all the tracks, across all the albums into one list. If you tap the list tab again, it will show playlists, which will allow you to pick specific albums. This unit employs Gracenote for track info. Well... while the artist/album/song titles are displayed, it won't show album art embedded in the file or images that are in the folder. I just get a white square with a musical note icon.
Sorry for the long post but, I spent the past week experimenting and scouring the interwebs for info and wanted to consolidate it for those on a similar search. Overall, I like the unit. It's much better than shuffling CDs and, the Garmin Nav is pretty awesome. For those that dig Sirius, that's got to be another plus. I just wish they had hired a usability specialist to go over this thing though...