Never had any experience with the W10 or UM Pro 10 since I'm not particularly interested in them so I'd refrain from comparing the IEMs.
Anyway where are you from? I'm pretty sure there are stores in Malaysia, Singapore and Indonesia that allow people to audition their products.
Do you by any chance have a Jaben store around in your country?
I do live in Singapore. We have a Stereo, Jaben (apparently the branch here is NOT so well reputed) and a Challenger (worst of the three). Stereo is quite far from my home, and making a trip over without getting a good idea of getting into is not a good idea in my opinion. The real question is: why then is W10 299 dollars while UM Pro 10 only 219. This price difference is SERIOUS to say the least, and very strange considering the MSRP's recommended are the same.