The S3/5s are definitely verging on the boring and slow in my opinion. I have never heard the SE versions. The s3/5's sound is pleasant but in no way exciting. You'll either love the lack of edginess or be bored to death.
(I was driving with Densen B100, which is quite a dynamic and transparent amp).
(I was driving with Densen B100, which is quite a dynamic and transparent amp).