MOG is great. The 320 kbps mp3 streams sound very nice at home on my PC>USB>NuForce Icon HDP Amp/DAC>Denon HD5000s and at work over WiFi or 4G (Wimax) with an Android HTC EVO>Analog output>HeadRoom Micro Amp>Audio-Technica ATH-50 setup.
With MOG, I can save any album or individual song to a "Favorites" list, and this list can be accessed and updated from any computer or device that can get to MOG's service. Any updates I make at home on my PC show up on my HTC EVO phone or my iPad, and I can add songs on my phone that will appear when I log into MOG on my PC. This synchronization is important to me.
The Android app I use with my phone is far superior in functionality to the browser-based internet GUI for listening to my saved "Favorites". The Android app will randomly pick 250 songs from my "Favorites" list, and it will cycle through all of them and add newer songs while removing recently played songs from the list that it generates. It seems very effective, and it does a great job of letting me hear all of my music now that I have built-up quite an extensive list of songs in my library. The PC version does not have a similar option available, and I have to manually put each song into the player if I only want to hear my "Favorites".
For music discovery, the radio is really neat with MOG, as it has a slider that you can adjust from "Aritist Only", which will only play songs from the same artist you have selected, to multiple settings in between that vary the number of similar sounding artists. So it acts a bit like Pandora, although it uses genres, and not Pandora's algorithm for matching acoustical characteristics, but it generally works very well. Even at the maximum "similar artist" setting, there does not seem to be enough variation when compared to the radio from my Rhapsody music service. It is still the best way that I have found to discover new music, and I can play an awesome find over and over again if I like, plus I can go play an album or the entire discography from a newly discovered artist. Any keepers can be saved to my "Favorites" in mid-play, so that I can listen to it later on any number of my MOG-enabled devices. (Roku media player, PC, netbook, iPad, phone, etc.)
While I have not had a reason to do so, there is an option to download tracks to an Android phone or iPhone when connected to WiFi, so that you can play back high quality songs when you are not online or in an area that you could stream the music. These downloaded tracks have DRM that locks the songs if your subscription is cancelled or you do not connect the device to MOG's service before your scheduled subscription renewal date expires.
It's not the only thing I use for my music fix, but I use it more than anything else because the sound quality is great and it is easy to access my music.