I am looking at both of these sets as well. Hitachi provides a link to reviews of both of these sets from its website.
http://www.hitachi.us/tv/discover/prodrev/60_VX915.pdf
http://www.hitachi.us/tv/discover/prodrev/17597_eprint.pdf
Both of the reviews are quite in depth, but neither of them address the glare problem you asked about.
In addition, other than the vx915 having firewire, what are the differences b/t these sets?
Hope this helped.
Does anyone have any comments or experience with this unit? I am interested in purchasing this or the Hitachi 50SV810 . . . I have read there are issues with the screen glare with the 810 that may not exist with the 915 but can't find any reviews of the 915 or general discussion. Anyone have any insight?

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