I would personally go for the RHA's, but then again I'm a bass head
(just a little). I'm not sure I agree with you when it comes to the se425's being "neutral" from my own personal experience with them. There are some sources that actually downplay the bass response of the RHA's (ex:
http://www.bestheadphonesreview.net/rha-t10i-in-ear-headphones/), and others that describe them as "earphones that can handle thumping bass" (ex:
http://www.pcmag.com/article2/0,2817,2368361,00.asp). I think it really comes down a lot to personal preference. The RHA's do hit a little bit harder when it comes to bass, but the se425's aren't lacking either. I apologize in advanced, I'm sure this probably didn't make your decision any easier lol.