In regards to the HD598's, I'm aware that I was comparing apples and oranges here; but as I mentioned before, personally, I find the M-80 superior to the M-100's(specially when you consider their value at ~$150 less than the M-100). Following this thread, I was under the impression that the M-100 would be a substantial upgrade to the M-80; naturally, I was expecting the same sound, but refined(more or less). Instead, I find they sound closer to a modified LP(which, as I mentioned previously, dont sound half bad with proper damping work; particularly for the $75 bucks they fetched a few days ago). About the Sound-Stage claim on the box; I actually found that an unmodified LP has a bit more air to the sound, than the 100's (although I must re-iterate that the bass and midrange bleed is unbearable in that state).
Now, what gets me is, when I was making comments on the Beats Pro not being a bad buy at $160, I had many people on my tail, more or less calling me nuts in regards to sound. Mind you, this is going out from memory(as I have sold the BP's long ago), but like the M-100's(and quoting Steve Guttenberg), the BP's had very wooly bass. The midrange of the BP's were a little odd, as some vocals had a tendancy to sound contorted(likely tuned that way to avoid piercing treble); never the less, the overall sound of the headphones left me with the impression that this is what a smoothed out M-50 would sound like. It really wouldnt surprise me if the M-100's would have endured more flack in our community, had they been branded by Monster or Beats.
Comparing the M-50's to the M-100's and regarding their SQ, I feel they trade blows; the M-50's sounding more balanced, where the M-100's have strangely conditioned bass(tons of slam, but very dry sounding; however, more control), and smoother/less gritty treble. For the price-portability, I dont see it as bad value, but I'd readily pick the M-80's, or DT1350 before taking another look at the M-100's. My main complaint about their credit to portability for me is their rather poor low-mid frequency isolation. In the end, I still find myself raising the volume in noisy environments, like coffee shops, train stations, and even planes. Comparatively, I find its isolation to be roughly on par with a well seated M-80.
In closing, I felt the comparison between the M-100 and HD598 was just, to point out where they stand in respect to fidelity. I cant give it points for their ability to reproduce a naturally sounding tone, I cant give them points for having authentic definition/timbre between instruments, and I definitely cant give them any points for sound stage or imaging. However, what I feel we're left with is a damn good sounding genre specific headphone. If you're looking for energy and thump for mindless listening sessions, then these will do you well; synthetically mastered headphones, for today's digitally synthesized recordings.
Your first point is kind of what I was getting at. I don't think that it's fair for people to be reviewing the M-100 based on what they thought the hype indicated the cans would be or what they wish had been developed rather than what the headphone is. That's like me taking a pair of HD-598's on an airplane and then writing a review about how horrible the headphones are because I couldn't even hear my music, but the guy next to me could. if you want neutral cans that are open backed for the widest possible soundstage then don't say that a headphone not even in the same category is crap because it doesn't meet those needs, just like I wouldn't call the HD-598's lo-fi because I can't use them on an airplane or while my kids are running around the house screaming.
I am not familiar with people jumping on you for beats pro at $160, but that hasn't been my experience on this forum. I have ready many folks say that of the Beats line, the Pro's aren't bad, but that they aren't worth the $400 (or more) price tag, but have told folks they got a good deal on some used sets sub $200. I have not, however, seen anyone say the Pro's are on par with the M-100s sound wise.
Lastly, on your points -- They aren't meant to be neutral sound reproduction, and the only reason you can't give them soundstage points is because you keep comparing them to open headphones. In a side by side comparison everyone I have let try the M-80s and M-100s immediately mentioned how much the soundstage was improved between the two, and the M-100s are considered to have a reasonable soundstage for what they are. We will agree to disagree regarding some of the timbre/separation as that's not my experience for the music I listen to, but I can see where some genre's that might be an issue.
Don't get me wrong - the M-100s aren't for everyone and I don't think that everyone should like the way they sound etc... I am the first to tell people if they want a reference headphone for use at their desk at home then to look elsewhere. However, I think it's unfair to say that they are bad headphones or "lo-fi" because they don't meet your needs. That's actually a common theme I am seeing too. Across nearly all of the reviews I have read the most positive ones are those that are in the context of the intent of the headphone whereas the negative reviews are people that think V-MODA should have made something else.