A streamer will effect music playback quality substantially. If one does not care about quality so much, then the "cheapest" may suffice, but really good Ethernet audio Renderers are going to cost something significant. This is an area of playback development which is moving pretty quickly, I feel that Ethernet Renderers with digital output (to a DAC), and Etherent DACs (with built in rendering) will supplant other methods of digital playback in the near future.
There are a lot of technical advantages to Ethernet distributed audio, and more and more homes are wired for Ethernet (at this point wireless is still a bit buggy in real world use, especially for higher resolution formats).
It appears to me that ROON is for those who really want the most possible information at their fingertips, it is pretty cool.