Nawazuddin Siddiqui pulls of one of the best performances of his career. He's fabulous! His body language, composure, magnetism & mannerism is at a different level all together. We don't come across actors like him often. If nothing else, watch the movie just for him.
Overall, depending on your political inclination, the values you carry, the principles you have, you may hate or like the film, as it is based on a political personality and the choices he makes. Personally, I must admit that the 150 mins did alter my opinion about Balasaheb Thackerey. That by itself shows that the film & the performance of its casts is good enough to have an impact (good or bad) on your opinion about the protagonist.
However, the film is very slow & if you can't read Hindi you might find it difficult to keep up. Dialogues at times are great but most often very confusing.
Bottom line is, if you are looking for a typical bollywood entertainer, you might like to skip this one. Else it is a good watch!