Guess it depends on your glasses. I can see both the 35mm and 50mm frames fine through mine. The 28mm frame is really hard for me to see with glasses, even by scanning; no problems if I take off the glasses and use a diopter corrector, though.
Incidentally, if you're shopping for Nikon diopter correctors, be sure you get the newer type with the small rim. Nikon also made an older model that has the correct thread size, but its large knurled rim interferes with a ridge on the R-D 1 body just below the finder eyepiece.