I can only hope that the original Karl May Shatterhand/Winnetou stories were a lot more entertaining that this cinematic adaptation! To be sure, the scenery is very nice (particularly near the end at Silver Lake), and the widescreen photography really captures the feeling of the open west. (Unfortunately, the only print circulating on this side of the Atlantic is in pan-and-scan.) The large gun-battle against the ranch fortress isn't bad as well.
If only the screenplay had been much better than it was! For starters, it has a curiously childish tone for much of its running time, similar to the kiddie westerns made by B movie outfits in Hollywood in the '30s and '40s. It goes on abnormally on (almost 105 minutes long), partly because of a slow pace - see how that stagecoach at the beginning of the movie rides on... and on... and on... and on... and on! Also, the story takes a number of diversions that bring the story to a halt, like when the heroes are captured. Not to mention some really laughable turns in the script, like how the heroes decide to take a women with them into hostile territory to look for the treasure. Still, it's fun seeing Herbert Lom in western garb, and this may be one of the only chances you see the INDIANS instead of the calvary riding to the rescue!