You should. The visuals are stunning, the score is highlights galore, and Henry Fonda is the ultimate villain.
This was one of few movies from the west that was allowed behind iron curtain, it became part of my childhood. I've seen it at least 15 times, it never gets boring even for a second. Timeless story, character, and the music... Leone/Morricone understood (in similar vein as George Lucas and others) that music can make one hell of atmosphere for the movie, much better than just awesome visuals and something mediocre in the background.
I like it even better than rest of Leone's movies, maybe a bit sentimental remainder from my childhood.