I was in a similar situation as you, deciding between er6i and vibes. I ended up going with the er6i because I wanted something to really isolate the ambient noise. I hear it's absolute necessity for those that fly, and I fly fairly often. Plus my roommates are annoying as hell so hopefully once my earphones arrive I won't have to hear them again.
I only know about the super.fi 3. Bellsprout called them bassy. I don't quite agree with that. I am no basshead and I have to compensate a little with the EQ settings on my Cowon D2 when using them. Apart from that they are REALLY nice. Good build quality, nice crisp and clear sound and quite pleasant to wear as well. I listen a lot to of indie too - and they work really well for me. I initially looked at the Vibes but all the reviews mentioned the punchy bass - which I find can be alright for cans but highly annoying right into my ear. I didn't pick the Etymotic because I noticed a lot of reviews and postings on boards mentioned that the build quality could be better.
So...if I had to choose all over again? I would pick my UE 3's again - but would like to try the Shure's for comparison. Good luck with you pick!