soundeffect, I personally didn't think you exaggerated about that ad700. I, too, thought they are base-light. The phone has emphasis on the highs, I personally couldn't adapt to the fatigue caused by it.
As long as you're fine with uniquely closed phone sounding, and if the dt250 fits well to your head/ear, then I think you experience so little fatigue that it's very suitable to your need.
If naturalness or neutrality is your ideal, then I'm honestly curious to know what you're going to say about the phone (pros or cons or both) once you got a pair and experienced it yourself. I think it says something when people who care about dt250 frequently indicate its "naturalness", "non-fatigue", "smooth tonality", or what's reflected in Saint Panda's "green tea" metaphor. My gut-level hypothesis is that Lunatique's definition of "fidelity" or "headphone nirvana" pretty much constitutes what people eventually realize as "natural sound" in headphones, and dt250-250 coincidentally come relatively closer to that than other entry-level phones.
Non of us here are Beyer's agent, so if you put dt250 on, didn't like the fit/sound, then move on for what suits you well, and no one here takes any offense. Oh yeah, one other thing, because the pad is velour in these, rather than a pleather, dt250 is free of the issue that the surface film coming off within a year or two of use.