I have been using the RNS-E as my radio for a few weeks now and I must say I am disappointed with the sound quality. Its probably less the quality of the sound and more that fact there is less control over the way the radio sounds. They symphony 1 had bass MID and treble controls while the RNS-E only has Bass and Treble. Also the symphony 1 had a hidden EQ which allowed granular control over the sound system. This EQ along with the debose option on the symphony 1 enabled the user to transform the sound system to produce harder hitting bass and mids with very clean treble. I really liked the sound of the symphony 1 and never thought it necessary to add anything to it, but with the RNS-E, I am looking at adding a possible crossover and an Amp to improve the sound. The navigation fuction and the Display of the RNS-E is phenomenal and a worthwile upgrade, I just wished the same control over the sound could be acheived.