I still appreciate my DT250-250 - they are a part of my home-studio sealed can rotation along with the AKG K271S and MrSpeakers MadDog. They are not perfect (that damn proprietary cable connection has caused me problems), but they are comfortable and have sound quality that scales higher than many closed cans. I would rank the sealed headphones in my current collection like so:
T50RP MadDog Balanced (sound incredible when driven via the Schiit Mjolnir)
AH-D7000 (sounds great with most gear, easy to drive - my gaming cans)
K271S/DT250-250 (they are tied overall and have different strengths)
What is striking to me is how terrible the stock T50RP sounds (to me) and how great the MadDog sounds in comparison. It amazes me how much a driver can scale with improved pads and other tweaks. Also, there is a difference between the 80 and 250ohm varieties of the DT250; I prefer the 250ohm version due to improved bass control and treble smoothness but they are harder to drive.
I was impressed reading your rankings. And then I re-read it and realized it was just your "sealed" headphones rankings. I then looked at your profile, and your "current" list of headphones, and then your list of "previously owned" headphones. It was at that point that my head simply exploded. Wow!
Anyway, I am looking forward to getting an excellent pair of modded T50RP's. So based on your impressions you never know, they might even make it to the top of my sealed headphone rankings lol!