I used to love my westone 2, but after listening to the sd3 I easily gave them away(to a friend of mine)
sd3 is the perfect in-ear for me:
sub bass is just right
mid bass(beat) is beefy, not BA-typical hollow,
upper bass is noticeable but not irritating like the westone 3 upper bass
the mids are just perfect, high resolution, nice separation, vocal presentation is the best I have ever heard-very emotional, instrumental separation is just as good as the vocals,
treble presentation is sweet, never too aggressive or sharp but the sd3 goes really high, it's just not the jh16 or UERM Treble which some people may like better.
excellent clarity, especially on the left and right channel
and the sd3 is not that difficult to drive, I have seen some RMAAs and the triple fi10s were much more difficult to drive.
the sd3 are very loud, like 17/30 instead of 20/30 with an Westone 2 or any other common universal in-ear.
all in all a big, full and rich sound, exactly what I was looking for, 445 Euro is a joke, if you consider their value.