Here's my gaming impressions post for MC450 vs M1570 vs HE400SE vs DT990. Again, thanks to everyone for the help and support in this whole process!
EDIT: I think I've made a final determination on the M1570's but I have some nagging concerns about comfort and sound signature and so I want to make sure they're my best option within my budget for my preferences. Can anyone recommend something like these except with a more "neutral" sound instead of the warm, dark tones? Or is that something that can be managed entirely by EQ?
Now that I've tasted this level of quality I'm willing to throw a bit more money at the problem, maybe up to $500 or thereabouts. If the answer is that the M1570's are as good as it's going to get without a huge price increase then I absolutely don't want "perfect" to get in the way of "very good" here and I think they could work. I just would rather spend the time now than burn $400 and find myself wishing for something different not long after.
Based on what I was reading someday I may splurge on the LCD-GX but at this point I can't justify nearly $1k on headphones. I read
@Mad Lust Envy 's writeup on the Shure 1840's but those seemed like poor all-rounders.