Surf or White winged Scoter in VT

[mfoster.vt]

Got these pics this morning at quite a distance.  I saw 2 male Surf Scoters in the same location, but this bird was swimming on its own quite distant from the males.  My sense is that this is a female Surf Scoter, but I can kind of imagine a white wing patch in one shot which might point to White Winged.  Another shot looks like it might have a darker cap, which would seem to point to Surf.  Unfortunately my scope is in for repairs, so I had to rely on these pics and my binoculars, neither of which had quite enough power.  Any help would be appreciated.

[sfinmt]

The dark cap, head profile, and facial spots arrangement look better for Surf scoter here.  I couldn't detect any white in the wings where it should appear on a WWSC.

[mfoster.vt]

Thanks sfinmt.  The more I looked at the photos, the more I was also convinced of surf.