So what's the current status of the MTW? STill no go? No updates to help?
No - Senn better get going to fix all the stuff they say will be fixed by the end of the month. MTW case still has drainage issues. I don't know about the 'crackle' because I never heard it, and as far as my colleagues are concerned, it's the second best sounding for calls behind the MW07.
My thumbnail sketch after two days of on-and-off listening to the M2, MTW and MW07. Remember these are relative differences - for example, I describe the MTWs as if they are more clinical, and they are when compared to the other two. But they're not ER-4Ps.
Overall, I think the MTW still offer the best sound profile, but I will confess it's a preference thing. MTW has more noticeable detail and "snap" to its sound (you could call this "harsh," or "sibilant" if you didn't like it) and slightly wider soundstage. Best way I can describe it is that the individual instruments seem more noticeable on the MTW, more precisely recorded and positioned.
MW07 in contrast has a really nice smooth sound without being cluttered or muddy. It's a less precise sound, but more "natural" feeling. It's slightly less wide and slightly less detailed, but it cymbal crashes and sudden noises won't make you jump if they hit you unawares. And they're so comfortable I actually forget about them. Overall, they're just nicer to listen to for a long period than the other two. Shame about the battery life.
M2 moves the vocal/mids so forward that the detail is harder to hear - it's there but in the background. M2's soundstage is smaller than MW07 or MTW, so sometimes it's hard to hear much other than the vocal track - everything is bunched together. The small, lightweight thing makes them comfortable but they move around a lot and have to be seated. This doesn't happen with the stock Complys, but those make the sound really muddy to me. The change to Spinfits made a huge difference - much more than on the MW07 or MTW.
I will confess that from track to track, my preferences change. M2 sounds great on something like an "unplugged" ballad, since there's not as much going on and the instruments are right next to each other. Something orchestral really benefits from the MTW detail. A heavy rock song benefits from the MW07.
Design-wise, MW07 has them all beat looks by a wide margin. M2 is the most "scifi" gadgety cool, though, with small size, the cylinder case, and the slide out. Both MW07 and M2 are conversation starters. MTW looks kind of klunky and cheap in comparison.
If the case actually
has battery, the MTW seems to recharge to full the fastest, followed by the M2 and last the MW07. Conversely, the MW07 case itself recharges the fastest and the MTW the slowest.
If I were sane enough to buy just one pair, I'd go with the M2 at the $175 sale price - the others are not enough better to justify nearly double the price. They're also the most portable. MW07's small case has to be covered in the pouch or it will look like you took sandpaper to it in days, which offsets it's realtively compact size. The MTW case is relatively huge and drains battery when moved. The M2 case is durable, well-shaped for travel, and compact.
Then again, if you spend a lot of time thinking about your hair and sunglasses, get the MW07 in one of the "colorways." People will ask you about them and deep down that's really what you want. Plus they sound great and are really comfortable, so need to suffer for fashion.
Sound quality aside, it's really hard to recommend the MTW due to it's overall issue set - I feel like we're beta testing them. If they get fixed, then it's a different story.
If you can swing it, I'd say buy all three and figure it out for yourself. You can easily return or sell the other two. At least that's what I'm telling myself.