The following from a post in the IndyFest09 threadd http://forums.klipsch.com/forums/p/116595/1220786.aspx#1220786

Professor Thump brought along a headphone demo case so I finally got around to trying the Custom 3 which are extremely sweet sounding, Image X5 (still  my favorite - awesome sound and really easy to use) and the new Image S4 and Image S2 which are still not available.  I was impressed by the new S4 and S2 - naturally they didn't sound as good as the Custom 3 or Image X5 but they also retail for $80 and $50.  Extremely good sound for the $.  The differences to me with only a couple of minutes with each is that the S4 and S2 are less refined sounding.  The S4 and S2 I'd kind of compare like the Image X10 and Image X5 - the S4 has deeper bass maybe but the S2 sounded a bit better to me though maybe just inclined to like it better as it looks kind of like a fattened up Image X5 while the S4 is just even chunkier.  At $80 retail the S4 should sell really well.  At $50 retail the S2 should sell even better. 

 At the time of the above post I think the Image S4 was available but the Image S2 still aren't but should be soon I think.  The Image S4 I think have dual micro speakers so will undoubtedly have better bass, but the S2 may have sounded better to me with clearer highs which is how I've compared the X10 (stupendous bass) and X5 (clearer highs and don't really notice that the bass is lacking) though the Image X10 and X5 are both single armature models.  

I've nothing new to add as my quick first impressions were from 3 weeks ago just thought I should post in Headhpones where it belongs.