I'm not trying to jack the thread, so if anybody knows of a better place for this, let me know and I'll move it!
Alright, so: I got some HF3s about a year ago (got a pretty good deal - yes!). I had some issues getting proper fit as they're the first IEMs I've used that go past that bend in the ear canal. I immediately liked the accuracy but I hated the feeling of wearing them for any more than about 20 minutes. I was using the silicone triple flange tips and had tried some of the others but just wasn't getting the best fit. I saw a great idea from Cotelio over at the thread Dsnuts made for the Monoprice 8320s. So I elaborated on it and got the best fit and sound isolation I have ever gotten from my Etys!
On the left are the buds that came with my phone. I put them there mostly to show what was going on with the black rubber on the HF3s at the right. I put a ring of earplug foam over the tips of the Etys first. Then I slid up the smallest rubber folding tips I had (for a pair of Creative EP 630s) around the larger part of the Etys. I put the earplug foam donut inside the rubber tips and folded the rubber back over the foam (since the rubber on the left is transparent, it should be pretty obvious how it works). I have the black rubber tips sticking partially over the skinniest part of the Ety's barrels. The tip of the Etys gets pure compressible earplug foam and voila! Now I can comfortably wear IEMs that weren't getting enough use because before this, I couldn't get a comfortable fit!
BOTTOM LINE: I've got better comfort, isolation, and sound from some great IEMs!