The RE0 has a totally different sound signature as the SF5 pro. The RE0 is more refined towards the upper frequencies while the SF5 pro is leaning more towards the bass area. That makes the RE0 bright sounding, providing more details while the SF5 pro is more warm and less detailed with more bass impact. The SF5 definitely provides more bass and if you're more inclined to bass oriented music then the SF5 will suite you. But if you like to listen to the details of your music (more analytical), then the RE0 is for you. I listen mostly to New age (instrumental) music and i really love to nit pick on the different sounds produced by the music i listen to so I prefer the RE0 over the SF5 pro. I owned the SF5 pro for over a year when the cord broke so i ended up buying the RE0. I was able to get a replacement cord for my SF5 pros but now i'm listening to my music using the RE0 90% of the time. BTW, I also love listening to electronic music and I have no problem with the bass production of the RE0. I feel it's just adequate and not overwhelming. I used to be a basshead but I feel that I have "matured" in a way and am slowly shying away from that preference. I think that the RE0 lets you listen to your music the way it should be listened to...Here's a rough breakdown of the frequency responses (in my opinion) of both IEMs
Highs (Treble) - RE0 - 5/5, SF5 pro - 3.5/5
Mids - RE0 - 3.5/5, SF5 pro - 4/5
Lows (Bass) - RE0 4/5, SF5 pro - 4/5
Although the SF5 pro produces more bass, i still prefer the quality of the bass produced by the RE0 and that's the reason why I gave it an equal value. Furthermore, the bass from the SF5 can at times be muddy and may override the higher frequencies especially in bad recordings. So it;'s quite obvious that I prefer the RE0 but in the end, it really boils down to personal preference. I used to love my SF5 pro by the way but when i got the RE0, i listen to it less often now. Cheers!!!
