I've had my FXT90 L2s for about 3 weeks now...love them! Got them from Accessory Jack and the shipping took a bit of time, but not anything too absurd. My Atrios were broken for so long that I got really used to my Senn HD595s, so the soundstage freaked me out for a bit as brain burn-in commenced, but the cohesive presentation and musicality of these IEMs is really just...heartwarming. I'm listening on an iPhone, no amp or nothin.
 
The appearance of the L2 champagne-colored version is really, really nice. The brushed metal-looking backing on the IEMs themselves is understated, refined, sophisticated...not at all "blingy" but not dingy by any means. Looks very NICE. Classy. The cable is...well, it's shiny. Hahaha...not much to say about that. They are nice looking as well. Slightly microphonic worn cable-down as I do, but nothing noticeable, especially with the clip in use and...you know...SOUND coming throught them (oh yeah, that little thing!).
 
Yes, engaging...yes, forward presentation. They are colored, to be sure, but one thing I love about them is the clarity and detail of the mids and separation that exists alongside the colorful, musical signature. Soundstage was cramped at best out of the box, but they are really burning in nicely and opening up. It's not wide. Average width (jury is still out, as they seem to be improving still). The depth is great though.
 
The sub-bass extension is really a lot better than I expected...coming from Atrios, that's saying a lot. I've got this sweep sine-wave file that just goes from 0Hz to something like 30k and the RUMBLE on the lowest end is phenomenal...it actually shakes my brain! Awesome. Musically, the bass has good punch although it's not SUPER tight and quick and articulate like the Atrios were...however, that's a bit unfair since they are one of them there bass kings. The FXT90s handle bass superbly, don't get me wrong. I will say this: the articulation has improved with the burn in time I've given it so far (I'd estimate ~100 hours maybe?).
 
The mids...well, it's not unfair to call these mid-centric, and this is where much of the magic and music of the sound comes from. Mids are up front, but not overpowering...they are just....PRESENT. What I love about this presentation is the detail and texture the mids have. I believe the punch and insistence of the mids, along with that texture, is what gives these IEMs a great 3D element to the soundstage. This is also where some of the separation is done and it makes an ensemble orchestral recording (Howard Shore, Nobuo Uematsu) a joy.
 
Highs are placed very well within the overall signature and shimmer. I wouldn't say it has that real treble sparkle...but they are not recessed. I expect they will open up a bit more with time, and actually I think my tips have a lot to do with the treble I'm hearing. No sibiliance, even with stuff like "What's the Use of Wondrin'" from Carousel or "Wishing You Were Somehow Here Again" from Phantom of the Opera, which would kill someone who is treble sensitive with the way those ladies hit their esses. Bright, sharp, but not cutting into your brain.
 
Anyways, that's my impressions. Gonna look around for tips now ^_^

I owned several pairs of the M5s (owing to the fact that I had them replaced several times through the warranty service). Never had a lick of trouble getting a replacement. I bought from an authorised reseller on fleaBay for a very decent price.
 
The design of these IEMs is quite pleasing to me. They are low profile, nice blue accent, sleek design. The cable is not at all fussy. The provided rectangular case is of a good size as well as quite durable. My package included a very nice assortment of tips, single through triple flange of 2-3 sizes each. Sure olives fit these IEMs as well.
 
I found them to be very comfortable for extended use using the stock biflanges. The olives I have provided a tiny bit more isolation, but I felt the isolation was good enough for my needs with the biflanges and the olives hurt my ears with extended use.
 
The sound...as many are aware, the bass response of these is quite renowned, and for a very good reason: excellent sub bass extension, quick, punchy, and full sound at low frequencies, and very little bleed into the mids. I wouldn't say the mids are necessarily recessed, although perhaps lacking a bit of detail or attention-grab from a more mid-centric IEM. The highs live in a similar boat, not forward yet not at all lifeless. These are not a 'sparkly' or 'bright' sound by any means, however I would not say the sound is extremely dark, either; rather, it's a decently flat sound with a warmth to it.
 
The soundstage, owing to the lack of shimmer on the high end, is a bit tight, although it has some decent depth. Despite the fact that things are quite 'intimate', I found the separation admirable.
 
Overall, the character of these IEMs is warm with EXCELLENT sub bass extension and terribly accurate and engaging bass response, with a pretty warm overall presentation and a fairly small 3D presentation. The upside is that you won't find bass like this anywhere else close to it's price range, and the presentation is not at all fatiguing. The downside is that it passes up a bit of detail and shimmer.
 
Future Sonic's warranty and customer service is absolutely wonderful, I might add. In the end, though, after tons of abuse, my 3rd pair of M5s bit the dust I believe because I may have stabbed the right driver with the earwax cleaning tool provided - there is no nozzle foam or grille between your eardrum and the driver on these, so use caution. This may be what the Atrio M5 owes a bit of it's amazing bass reproduction to.
 
All in all, an excellent value, and although the MG7s have now usurped the M5s, these were fabulous IEMs.