I agree with the comments on the size of the UE 5 Pro EB. I don't find the size of the standard UE 5 Pro to be a problem.
I'm afraid I can't comment on the WestOne's or q-Jay's as I haven't personal tried them (we don't stock them yet - both coming soon though!).
Another option is the new
Sleek Audio SA6 in-ear earphone. We've just started importing the SA6 directly from Sleek Audio. The SA6 is a really miniature earphone and is a very easy and comfortable fit compared to any of the Ultimate Ears and Shure in-ear headphones.
I've been using the Sleek Audio SA6 daily for the last month or so and I have to say I'm very impressed. The SA6 was an upgrade from a pair of Shure SE310's. As far as sound quality goes the Sleek Audio's are easily on par with the SE310 and UE Super.fi 5 Pro - in my opinion the easier fit and customization ability makes it a much better earphone.
I was a bit concerned the bass would be lacking on the SA6's as they have a single driver, but I've been pleasantly surprised. With the largest bass port there is plenty of bass for me.
Shaun