Yea the E17 should suffice. You should be able to demo the m100 at Brookstones store (a US store) if you haven't already heard it before. D7100 is super comfortable also. Not sure about the fit of any of these given I have a large head myself. Also keep in mind that I am in the minority for my opinion on the m100 so u should definitely demo it yourself.
I have a pair of M100's already. Leaning towards the HD700 at the moment, since I know Sennheiser usually keep the small headed in mind. I've never had a problem with Senns before.
These aren't larger than the say, HD 650, right?
Still nervous about whether or not the E17 can drive them properly.
What's nice about the D7100 is that they're so easy to drive.