Such an anime seems like it would get boring quite quick. A perfect protagonist, after all, cant really grow. And here's where the similarity with OPM is most significant. Both tell the story of their protagonist through the side characters. In OPM most of it's about the public not recognizing Saitama, and how other heroes cope with his superiority. In Sakamoto desu ga? it's about the other students, and how they deal with this "freak". However the similarities end shortly after, with OPM delving into juxtapositional comedy, and Sakamoto desu ga? focusing on more altruistic, almost philosophical comedy.
The art and sound are relatively standard for the most part. When it wants to, Sakamoto desu ga? can hit you with some beautiful visuals, or masterful songs and dialogue. However those moments are reserved, and given as "rewards" for reaching the climax of a story.
My main issue with Sakamoto desu ga? is the story structure. Each episode is broken into 2-3 "parts", with each part being ~10 minute "adventures". While this is great for comedy, it's very hard for the show to develop many characters, as they simply don't get enough screentime. This leads to Sakamoto desu ga? at times feeling void of personality, but that almost never detracts from the comedy within.
All in all I loved Sakamoto desu ga?, and it's a show I sincerely enjoyed. The humour was spot on, it was just light enough while remaining serious on some issues, and Sakamoto was amazing, without feeling robotic or devoid of humility. Like OPM and Mob Psycho, this is a comedic classic I'd wholeheartedly recommend you give a watch.
