I'm not much of a high-fidelity listener and have been perfectly happy with the B&O earbuds for the last few years, because they're fantastically comfortable. Last week I picked up the Triport IEs with only modest expectations and haven't burnt them in yet. Some first impressions though.
The IEs are, as people are saying, pretty comfortable to wear, even for long periods. Although they don't isolate, they do block out a lot of background noise and can handle high volumes without sounding embarrassed. They fit well enough into my ear to have noticeable noise from the cable, and stay put once they're in place. Interestingly, there is incredibly little "leakage", so people around you will not hear any annoying wasp-buzz. Even if you take them out of your ear and hold them close to it with music playing on high volume the IEs are almost silent, which must say something about how well they direct sound into the ear passage.
The IEs are moderately difficult to drive; I listen to them with my iPod on full volume, which I never used to do with the B&Os. This means that the limit is very much your amplification ... with the high output on a plane journey, I found that the IEs were fine to unbearable volumes. I don't own a headphone amp, but would guess that those who do would be happy with the impedance ... the rest of us will probably end up topping out the volume dials more than we would like.
In sound terms, I initially found the bass, which is startlingly emphasized, to be too "boomy", with a sense that particular frequencies were being given inappropriate prominence. Since that first impression, though, I've noticed how good the IEs are at bringing out sustained low notes. Bass guitar is great, the IEs separate acoustic bass from guitar well, synth pads have added richness. More impressively, the IEs brought very clearly a deep gong sound that is usually disguised by cymbals in a Messiaen piece.
On the downside, these are not (at least, without being burnt in they're not) the sort of headphones that flatter everything that they play. I try to avoid EQ on playback, but find a degree of treble gain essential to get any airiness into the sound. Thus far I find that mid-range instruments, especially guitars, lack presence, and the swollen bass drags somewhat on rock mixes (e.g. Springsteen's "Thunder Road"), robbing them of immediacy and excitement. Don't expect much to show for your money if you listen to music that is naturally lacking in bass.
By contrast, these semi-earbuds do a great job on dance mixes where the relatively separated bass line can be blown up almost to nightclub intensity without losing the rest of the track. The same trick works well on orchestral music ... although the IEs aren't doing anything special at the top end, they retain an acceptable level of mid-top detail while adding a bottom end that you simply don't hear much except on high-end hi-fi systems or heavily coloured home cinema systems.
In terms of build, where you'd expect the IEs to be pretty flawless, the critical element (the headphone jack) looks up to the job and the cable seems well secured at the headphone end. The connection between the soft sleeve and the main earbud is not as positive as I'd like ... I fully expect the sleeve to be left in my ear when I remove the bud, although it hasn't happened yet.
The carry case - very bulky compared with the B&Os - looks great but I find winding up the chord something of a pain. On the plus side, you will not damage your IEs while they're in the case because they are protected by hard plastic inside the leatherette.
I'll post more if my view changes over time, but for now I'd say that these are well worth the money.