I am interested to understand how you decided its user friendly, what apps have used to compare?
i found it very un user friendly, the buttons are a mess (is it a java app?) and often clicking a button resulted in nothing happening.
I've used iTunes, foobar, mediamonkey, LMS and a few others. JRiver let me organise, play and browse my music the way I want to, and did so very easily. In particular I can organise my classical music sensibly. From my pov it is in a different league from other media centers. I've never found a button that didn't work, and wouldn't agree that they are a mess. I have only used it on a pc though - perhaps you tried an earlyish mac version and encountered some problems. And it is probably still a better fit to the windows world than to the apple world. Did you ask for help in their forum? ime you usually get an answer from a developer within a day. But the real icing on the cake for me is JRemote - the iPad control point app. It is absolutely superb imo, so the combination of JRiver and JRemote is for me a real pleasure to use.