OK, got a request to compare the Sony XBA-3 and the UE Triple Fi 10 (T.R.A.N.C.E., I believe), so here goes...
I was actually a bit surprised at my own impressions as I was listening. It's a bit difficult to go comparing 2 iems that you like (actually, not all that difficult, jumped out at me first listen, but I was surprised).
Anyway, start with fit-Sony (to me, this area varies person to person quite a bit), never had any trouble with them, easy shape, fit nicely, good isolation (but not up there with Etymotic), can keep them in for a while without discomfort.
The TF 10's were the first oddly shaped iem I dealt with, and for the longest time I couldn't get a good fit, couldn't get comfortable with them, couldn't get a good seal. Now there are even more oddly shaped iems out there, many much more unwieldly, with chambers, stops, square bases, you name it, and the TF10's no longer feel so clumsy or difficult to use. I actually have had these sitting most of the time unused because of comfort issues, but seem to gotten a pretty good fit with UE large silicon tips, and have used them a bit more recently. Still, less isolation (in my ears) than the Sony's. I'd say I've pulled the Sonys out much more than the UEs when just reaching for something to play.
Now, the sound. I like them both, but the UE is one of those jump-out-at-you headsets. I found it did larger soundstage, quiter space between instruments, better detail, and great rhythm/coherence (that WORD). Highs are well defined, with good cymbal sound, not tizzy (to me), and just exciting to listen to. The Sony's, which I like, don't have as wide a stage, seem more dense than the open UE, as a result, detail, which is there, is harder to make out...you have to listen to pick things out, rather than them just being there. The Sony has a bit more midrange presence/bloom, with vocals slightly more front and center (but the UE's don't bury them, they're easy to hear). Bass presentation is pretty similar, both having good, full bass with good bounce and presence. (as an aside, the Sony's are a bit less sensitive, and need the volume turned up a bit more, but not enough that it should strain the player or need to be all the way to 5 O Clock). I'd say the UE has more "wow" than the Sony, best way to describe it.
So, if the price is similar, I'd say, go TF10.