I got both to review and I gave them both 5 stars.
I personally liked the Comet better because it was better at g-spot stimulation and it was a bit thinner. Being a girth wimp who likes curved silicone toys the Comet was just a better fit for my needs.
On the other hand, I am really glad I tried both. They're both made of great materials and are very different toys, so there's certainly a reason to get the Comet a friend.