I do not know if this is the greatest punk rock time travel novel because it is the only one I have read. And the punk rock part did not seem that central to me. I did find the battle between the two groups through time over the rights of women to be fascinating. There are some shocking bits of violence that are part of the story but do not always resonate well with the general tone of the novel.
I did recently read another time travel novel, The River of No Return, and found it far less enjoyable and satisfying than this one. It seemed to lead up to something and then just ended. The Future of Another Timeline definitely delivers.
The time travel device itself was a bit strange and the back story on where it came from (super prehistoric past, apparently) and who built it (we never know) leave the reader wishing for a bit more. However, that does not detract that greatly from the story you do get. The parallel stories in different time frames become clearer over time and there is a major reveal (or plot shift) in the middle of the book that requires one to go back and rethink what has been read. I found it made me think about in what sort of world do we really want to live (who has rights, who is subjugated). It is frightening to think how some of these exaggerated views and efforts by reactionary forces to turn back the clock resonate in the actual world in which we live. We cannot go back and build new timelines but perhaps we can do a better job of constructing the future we can have.