Let me simply input my 2 cents worth of opinions here.
It seems like the TS has been changing his mind about which to get.
My reading on head-fi suggest people looks for either headphones or iems, a matter of whether it is portable or not.
I haven't seen much people comparing headphones to iems and deciding to get either.
It's either the portable boat or the home equipment boat.
That said, headphones to me are superior in most ways, especially open ended ones which not just provide
excellent technical sound quality but also more coherency and soundstage.
When you're at the high end of audio equipments, you're already looking at technically superior headphones/iems.
The deciding factor would be the type of sound signature you prefer.
Let's say you want to do recording, TS your UE18 is an excellent choice, since you already have a reference monitor,
why not option for a more "Fun" sounding iem?
With your affordability, you can look thru not just K3003 and IE800, but also fitear TG334 as well as tralucent 1+2, and
even the upcoming SE846. It's better to audition everything within your means, than regret after getting the iem you thought was best.
That said, I own the IE800 myself, I do the teabag mod as well as -3db on the 100hz region. It sound pretty good to me compared to
an unEQed and unmodded IE800. I too have listened to both k3003 and ie800, I decided on the IE800 because of the "Fun" signature.
I will have both 1+2 and TG334, as well as SE846 to listen to, I hope ill still be loyal to my IE800 by then.
All im saying is you might want a "fun" signature sounding iem instead since you don't find your UE18 particularly enjoyable.
On a side note, excellent write-up on both iems in your previous posts.
Edited by muscular - 7/21/13 at 11:16pm