[leftnose]

So my Klipsch X5s finally wore out after at least 5 years in service.  I'm thinking of getting a set of Westone UM Pro 10s to replace them.  I know that they'll be a bit more neutral than my Klipschs ans I'm OK with that.
 
However, how do the cables run on the Westones?  I know they're up and over but are they down the chest like Shure/UE or behind the back?  I've never been a fan of down the back and I can't find any info on this online.

 

[tomscy2000]

There's no cable that specifically runs down the back or down the chest.
 
All cables work either way, except for remote/mic cables, which cannot be worn behind the back.
 
For earphones that have a split length 'y" design a.k.a. "J-cable", they have to be worn behind the neck, but the portion below the Y-split can be slung in front or behind. Usually, these earphones aren't the over-ear only style a la Westone/Shure/UE.
 
The Westone will have a equal length braided cable. Unless you don't use a smartphone, I'd actually recommend getting the W10 instead of the UM Pro10, because they include two cables, one with a mic/remote, and one without. The Monitor Vault is also good for storing them. I don't think you get these luxuries with the Pro10.

 

[leftnose]

  There's no cable that specifically runs down the back or down the chest.
 

 
I disagree.
 
The distance from the IEM to the "Y" joint will dictate where it can run.  If the legs of the Y are shorter, you can't run the cable down your chest as it will catch on your throat.  Such cables have to go down your back.  Cables wtih longer legs to the "Y" can run down the chest.  Before my X5s, I had UE TF10s.  The OEM cable had a long enough "Y" that I could run it down my chest.  A popular mod at the time was to put Westone cables on TF10s.  I tried it, the Y was too short to clear my neck so the cable had to go down my back.  As I mentioned, I don't like that so the OEM cable went back on.

 

[tomscy2000]

  I disagree.  
The distance from the IEM to the "Y" joint will dictate where it can run.  If the legs of the Y are shorter, you can't run the cable down your chest as it will catch on your throat.  Such cables have to go down your back.  Cables wtih longer legs to the "Y" can run down the chest.  Before my X5s, I had UE TF10s.  The OEM cable had a long enough "Y" that I could run it down my chest.  A popular mod at the time was to put Westone cables on TF10s.  I tried it, the Y was too short to clear my neck so the cable had to go down my back.  As I mentioned, I don't like that so the OEM cable went back on.

 
Yes, it does depend on your height/weight and general build; but in that case, you'd have to try it yourself. Cables from these manufacturers are designed to be worn either way, regardless of the length from earpiece to Y-split, but they won't account for people whose dimensions differ from what they set for as an "average" person. You should measure yourself and determine what length of cable is acceptable for you to wear down your chest and then proceed to send Westone customer service an inquiry regarding the length of their cable from earpiece to Y-split. Perhaps you could also ask people on the forums to measure that length for you. However, whatever length is acceptable to you was not disclosed in your original question, so people would not know how to answer you in a complete manner.