Best film is for the most parts subjective and while I don't have a favourite film as such; I can't stop loving Conan Barbarian as the best CBM film I can think of, sure it has it's glaring flaws but how I love those beautiful action scenes and the music score of that film... Gerry Lopez, Sandahl Bergman and Arnold do them all like Ultron says "there's are no stings on me" and not a drop of CGI... *sigh* practically nobody does such crispy, realistic & visceral fighting in films any more. It's all just CGI, shaky cam & wire hopping these days.
Completely different styles and tones. The Winter Soldier has much more watchability while watching Requiem I feel like I need a shower afterwards. Requiem though holds a sentimental place for me that no other movie could top though