This version of Lerner & Loewe’s story about two men searching for gold, alcohol and a spouse is pretty good. Clint Eastwood, playing the more restrained "Pardner," comes across surprisingly well; it turns out he can sing alongside Lee Marvin, who is excellent as the grumpy “Ben Rumson.” Things get interesting when a Mormon man shows up in "No Name City" and decides to auction off one of his wives. Marvin buys one, and soon there’s an unusual but friendly arrangement with Jean Seberg – the practical "Elizabeth" – as their wife. The plot does move slowly at first, but the three main actors, supported by some beautiful music (Nelson Riddle arranged “Wandrin' Star,” "They Call the Wind Maria," & "I Talk to the Trees"), do a solid job, even if Marvin’s singing isn’t perfect. You can tell the performers are enjoying themselves amidst the rain, dirt and hardship – and that enjoyment is often infectious; there are some really fun group scenes and musical numbers too. However, the narrative feels stretched out over what felt like an extended period of time, and while there are a few clever lines, the humor also seems spread thinly throughout this nearly three-hour film. The final ten minutes are quite impressive from the art department’s perspective as things circle back to where they began. It's generally enjoyable entertainment.

Source on TMDB