1K speaker advice?

I am looking to upgrade speakers from Dana Audio 1s to something full range with better resolution, with about $1K to spend. I have a NAD 100wpc power amp. I listen mostly to vocals, acoustic music, and blues - and to a lesser degree jazz, rock and classical. A local audio store has a used pair of Thiel C2 at $700. They sound great but I'm concerned about the age and how they will sound with my front end equipment. Am I better off buying something new - if so I welcome suggestions.