I know that you are interested in the Westone UM3x, but you may want to keep in mind that there are sonic differences between the Westone 3 and the UM3x to not confuse the two. From what I understand the UM3 are more for listening to music and the UM3x are more for monitoring. They recently (as in a couple years ago) introduced the Westone 1, 2, 3 series as earphones that are more aligned to listening to music than the studio monitors of the UM1, UM2, and UM3x. I have the Westone UM1 and the Westone 2 and the two sound very different, and not only because the Westone 2 is a dual-driver design. The UM1 are much more neutral and have a more forward midrange, while the Westone 2 have a more rolled-off bass and a relaxed midrange. I like them both, but they are for different applications.
I really, really want to purchase a pair of the Westone 3, as the reviews on them have been outstanding. Just a bit outside of my budget for now and I am really happy with my Westone 2 earphones.