Without a doubt, I would look for a used pair of Paradigm Studio 20's. Version 1 or 2.
Best speakers for $500 or less
I have a friend who wants to get a good pair of speakers for $500 or less, and was looking at Bose. I cringed. Though Bose does make some OK speakers for a very small size, I thought there is probably something better out there and I would turn to all the good Audiogoner's to help! My friend listens to a mix of 2-channel and TV/movies, and is looking to get two speakers now and expand later. What would you suggest???