[franko]

In a few days I plan to try some IEM's at one of the higher-end audio dealers in our area. They say they carry both models by Cardas (which I assume would be the EM5813 and the A8) as well as several by Westone.
 
Has anyone tried these and, if so, do you have any thoughts on what I can expect -- how the different models compare -- and/or any points to look out for?

 

[ProtegeManiac]

I wouldn't get into the sound too much as that contributes to confirmation bias, but one thing you need to test on both is comfort. Put them on and listen one after the other per track to test for sound, but try to listen to each for three tracks at a time. If either is uncomfortable after three tracks then chances are that will only get worse for longer periods vs the other.