I don't know it there was a huge difference in SQ, but I do like the Westone's flexibility... it hangs like a silk thread with no memory whatsoever. The stock UE cables got hard within a year and I wasn't privy to this website by the time I'd ordered more, much to the same effect in about as long.
No, the Westone's don't fit exactly, but the thread here that convinced me to try them explained very clearly how to trim the tips and make it fit (though the pin diameter is larger and you won't be able to go back to stock afterwards, also mentioned in that thread)
In another thread here, two users have already had pins break off in their TripleFi's sockets with the Fiio cable, rendering them useless. I'm not bashing Fiio - I own several of their products, am happy with them - but just passing along the info in case you hadn't heard it.