Terribly old fashioned, but somehow wonderful.
When I first found this one, I ignored the exercises and went straight to page 28 with the nice interlinear text.
Given the relative linguistic conservatism of the *written* Armenian language(s), it's "useful" even to those who want to learn contemporary Armenian.
Caveat: You have to be comfortable with the altdeutsche Schrift, or learn it just for this occasion.
And yes, I'm a fanatic admirer of Sayat Nova, not just because of the movie.