i tunes vs. j river in pc realm

I own a PC and just dipped my little toe into the "computa" music server world having purchased a fairly inexpensive (but good, I think) DAC from Kingrex. Installation was a breeze and I'm listening to Pandora, LastFM and Wolfgang streams as well as purchasing tracks off I Tunes. I'm hearing that J River is an improvement over I Tunes. Can someone please explain if this ONLY comes into play during the "ripping the CD" process (which I'm not doing yet) or if it comes into play whilst just listening to the streams mentioned above. Also, what is it that J River does better?
J River CAN sound better set up properly as it gets a lot of the computer out of the way via ASIO or Kernel Streaming. But you are streaming low resolution sources anyway, so it likely won't make much difference at that stage in the game. If your gonna rip, don't use lossy compression. dBpowerramp is great for ripping.
If you get the current version of the free JRiver, you won't be able to use kernel streaming or secure rips. IIRC you'll have to find V12. JRiver Media Center, like iTunes, is overkill for just playing/managing music files.