Somewhere in Time is still very good, but it falls short of the first five. It's where the choruses started to get a little more repetitive, the songs a bit overlong, the energy a bit less, etc. SSOASS is riffless and only has some excellent leads and guitar harmonies to save it.
And while Where Eagles Dare is my favorite Maiden track period, people that treat Quest for Fire or Sun & Steel as if they're actually bad songs don't know what they're talking about. Every song is excellent on that one.