Note: Skip to the end for the short version.
Thanks for your harsh criticisms, you really saved this thread from going dead. You're right, when I wrote this, I didn't have that much experience; it was actually my first step into the audiophile world, but that's not to say that I have considerably more experience now. I've tried 3 more cans since the SRH440 and I do have to say the SRH440 were very good headphones (with the two years that I haven't heard them. My only really clear memory of them is from the song "Passion -KINGDOM Orchestra Instrumental Version" in flac), which I don't think I highlighted that much in my initial impression, but my later postings should have made that clear. However, there are a few things which I will not yield on from my original impression:
1) These headphones are not for bassheads. If you honestly believe a basshead would enjoy these headphones as much as the MDR-XB700 (or the Audio-Technica A700 or Beyerdynamic DT770), then it's clear that you aren't a basshead, and you may not know any real bassheads. Sorry for the harsh tone, I truly mean nothing by it. To make my statement a bit more objective have a look at this graph:
I'll say this again, and for the last time, since you're not the first person to say something like this: these headphones are not for bassheads. They weren't engineered for bassheads, they're not marketed to bassheads, they don't sound like they're made for bassheads, they don't like they're made for bassheads (IMO), they're not for bassheads. Stealing this from Shure's website: the SRH440 is engineered to "reproduce accurate audio across an extended range." That, they do. I believe I even mentioned that these headphones can go as deep as the XB700, but nowhere near as much quantity. If they SRH440 did have as much quantity as the XB700, DT770, A700, and so on, then I could sue Shure for false advertising. A bassheads can is the antithesis of that statement.
2) Games
in general don't have clean audio tracks; they're loaded with bass and brickwalled to kingdom come. For TV shows, the sound is biased towards cheap television speakers (but movies are okay). I like the MDR-XB700 since it's not very detailed and the crappy sound quality from games and shows doesn't make you cringe as it would coming from the SRH440 or DT770, which are both very detailed. Coupled with the fact that the SRH440 is bass light when unequalized, and you're in for a not enjoyable gaming session. I still recommend the MDR-XB700 over the SRH440 if you're going to buy cheap headphones for gaming and TV shows.
3) If you don't have a decent source (a laptop sound card and integrated desktop sound card qualifies as a not decent source, unless you spent your money on the good stuff), you should not get these headphones. These headphones sound very good for their price, which means you'll also have to spend a proportional amount of money on other audio equipment if you want these to sound even somewhat good. Portable MP3 players are pretty much mobile DAC/AMPs with a flash storage chip and an efficient CPU; more money goes into the audio components of an MP3 player than it's "computer" parts.
I have actually listened to the ATH-AD700, but it was only a brief time as the cans belonged to a friend of mine. They sound quite open, but it would be a shame if they didn't considering they're open headphones. As far as matters of reference go, using a different set of cans would not have changed my overall view of them. Consider this: voltage is a measure of potential difference, the difference part implying that it is a quantity measured between two points. If you have a source of charge, and you put it in contact with varying sources of charge with different characteristics, you will get different voltage potentials depending on whatever secondary source you put it against. However, this does not change the nature of the first source of charge. The same is true for headphone listening. If I had listened to the SRH440 now, compared against the ATH-A700 and DT770, I would have written a harsher review and I would have returned them immediately after writing the impression. That doesn't change the fact that for $90, the headphones are very good, or that they sound boxy unequalized, or that they have lots of sibilance unequalized (actually, the A700 and DT770 both have more sibilance unequalized. The DT770 so much so that it actually hurt my ears the first time I listened to them), or that they have great frequency extension, or any of that. So, if you think that I wrote an unfavorable review of these headphones because I used the MDR-XB700 as a reference, just consider how much more scathing it would have been had I used the DT770 or ATH-A700 as references (it wouldn't have been much different, considering that it is only $90).
And as far as the XB700 being "bad" headphones, I don't think they are. They have horribly recessed mids (compared to the DT770), lack any open quality (compared to the A700 and SRH440), and lack soundstage (which is a term I now understand thanks to the DT770). I would recommend the ATH-A700 over the XB700; they sound like the mix of the XB700 and SRH440 that I always wanted. In fact, the DT770 is a further improvement on that mixture by having a good amount of bass, comfort, and sound quality. However, the new street price for the DT770 is about 3 times as much as the XB700, and 2 times as the A700, so those aren't very fair statements. The XB700 doesn't sound considerably worse than the SRH440, and bass heavy instruments (guitars, cellos, drums and taikos, etc) sounded much better on the XB700 than SRH440 (I remember not enjoying "Chain," by Back-On, on the SRH440). So, it's really a matter of preference. If you're a basshead and want something cheap, get the XB700. If you're a budding audiophile, get the SRH440.
Short Version/Summary of this post:
1) The Shure SRH440 is not for bassheads. But then again, it wasn't designed for that purpose.
2) The XB700 aren't bad headphones; one should qualify what one means by "bad" at any rate.
3) Don't beat a dead horse.