I have got some Polk db650's gathering dust in my garage if anyone wants them. I have 2 pair. I think they were great, but replaced them with Wetsounds and thought the Wetsounds were better.
I think something that has been stated but not directly, is that it is really important to get enough power to your speakers. I think that is not likely to be the case with your clarions, but if you find the new speakers to be lacking, make sure you have a powerful enough amp to push them.
Be excellent to one another.