Wow, E500 is on Drop now. I got one for free when I joint an Acoustic Course held by Final in Akihabara a few months ago.
For my Oculus Quest, it sounds very immersive. While using it for music playback, I consider this to be the most balanced sounding earphone among the whole E-series. It is not an earphone which is very focus for detailed sound like most of the BA earphone does. It provide a very soothing and convenient sounding. Looks like the direction that Final is taking recently.