Nope, the Z1000 doesn't sound the same as the 7520. They're distinctly different (I've listened to both). The bass is very rolled off on the Z1000, which is the biggest difference between the two. Testing the Z1000 will not really give you an impression of how the 7520 sounds. The mids and highs might be somewhat similar, but that's about it.
That's what scares me now, I listened to some Z1000 at a store in Tokyo, plugged them into my iPhone, and the treble was so bright that it was practically shrill. I couldn't stand it, and took them off right away. Is this really what the 7520 treble is like? If so…no thanks!