I agree that it's a great introduction to Nietzsche's philosophy, and Durant does a good job of explaining Nietzsche's ideas in a clear and concise way.
I also agree that some of Nietzsche's ideas are quite extreme, and I can see why you find them toxic. However, I think it's important to remember that Nietzsche was a complex and contradictory figure, and his ideas should be interpreted in light of his entire body of work.
For example, Nietzsche's views on women are often cited as evidence of his misogyny, but it's important to remember that he also wrote extensively about the importance of love and compassion. In fact, some of his most famous passages are about the need for us to overcome our egotism and connect with others on a deeper level.
Ultimately, I think it's up to each individual to decide what they think of Nietzsche's ideas. There's no right or wrong answer, and it's important to be open-minded and willing to consider different perspectives.