This is definitely a 5 because I love Atwood's style - I always devour her books. I also love Greek mythology, and The Penelopiad is Odysseus' wife's side of the story. It's a pretty read but not much happens. If you like poetry and looking at flowers, or are a particular Margaret Atwood fan, definitely read it. If you would prefer something fast-paced and plot-driven, you'd be better off reading The Odyssey.
I sometimes think of books like these as mythological fan fiction. Do you have a favorite mythological story? Or have you read some mythological fan fiction that you found particularly good?