thomas, I think the RS-2 generally has much more treble then the RS-1s. They have a similar wooden coloring to the sound, but I've owned both the RS-2s and RS-1s before, and the RS-2s were MUCH shriller in the treble. On the other hand, sibilance is pratically at a dead zero with the RS-1s.
Anyways, now that Apheared's posted about the 325s, all I can say is...I told you so.

I still maintain that they sound fine out of my MD player, I mean I have used the two things together before and it sounded just fine...you want bass, use the bass boost!
There is another very serious competitor I must say though for this category, and that'd be the Sony CD-3000s...which can also be driven from a MD player. They cost $100 more, but for dance music, it's good to go. It packs much more bass wallop than the SR-325s, and has a crisp treble as well.