Got my TF10s yesterday, thought I'd do a quick compare against the 262s.
The mids of the TF10s, in my opinion, are pretty good when examined objectively (as in independent of the bass and treble that overpowers the mids). They are very clear and you hear every detail in the mids. However the TF10s cannot match the way the RE-262s renders the same vocals, the 262s are just more life-like, they give body to the vocals. But as I mentioned, the mids take a back-seat by design in the TF10s.
In terms of soundstage, there's no comparison. The 262s are better in every regard, depth, width, placement. Going to the TF10s is like going to Grados from the Senn or Beyer cans the 262s are.
The 262 highs are very recessed, you do hear almost the same level of detail in the highs from the 262s as you do from the TF10s. The reproduction of the highs is very artificial and doesn't have the same satisfaction the TF10 highs give.
I didn't expect this but I like the lows of the TF10s better than the 262s. I thought since the 262s are biased towards the low end being warmer phones, that they may just do the lows better than the TF10s but that's not the case. The TF10s make the 262s lows seem thinner.
The 262s have the TF10s beat in every other area: build quality & comfort.
I mostly agree with your impression of the Triple.fi, except that for my ears they are actually quite comfortable, but my outer ear canals are pretty large. I also agree that Triple.fi actually has very good mids - they are just overpowered by the mid/upper bass and treble with the wrong tips. I found that Triple.fi offers a very nicely balanced sound with Sennheiser IE/CX series IEMs single flange silicone tips. They are softer than the stock ones and provide a more delicate sound and also bring out the mids nicely. I also think Triple.fi looks really cool. lol