I haven't listened to the TDKs, though I do have the R-50s which are similar though probably a bit thinner than the TDKs. I'd be surprised if the soundstage was bigger on the TDK's vs. the EPH since the R-50s don't touch the EPH in soundstage. For house and trance, the EPH's sub bass and 3D-esque imaging work extremely well. It is one of the genre's that really takes advantage of the Yamaha sound... the other, strangely enough, is acoustic folk music.
The key advantage to the EPH in my mind (not sure about the sensitivity of the TDK vs. say the R-50) is that they just don't need an amp to sound awesome. If the TDK's, using the same dual-BA system as my R-50s, have a similar sensitivity, then they really capitalize on amping whereas the EPHs just sound good from any power source.