Before I found pairs of Polk SDAs the Monitor 10s were my favorite speaker. They are a nicely balanced 2 way with passive bass radiators instead of ports. They are a great match for vinyl and can be found at good prices. The Monitor 7s (Matt Polk's favorite in the Monitor line) have better imaging but I preferred the lower bass extension of the 10s. The ones with Peerless tweeters are more sought after; later models use Polk's SL-1000 or SL-2000 tweeters. These have spike at about 13kHz which can make them shrieky as they age. Fortunately Polk makes a replacement RDO-194 that fixes the problem. Join up at Club Polk (
http://www.polkaudio.com/forums/) for a discounted price of about $50 each.
Since these speakers are over 30 years old it is a good idea to rebuild the crossovers with new caps and resistors. You can get lots of detailed help for this at Club Polk, also.
I paid $90 for a pair with the SL-1000 tweeters and Polk stands, replaced the tweeters with RDO-194s for $100 and so had a great pair of speakers for under $200. For another $100-200 I could rebuild the crossovers for even more improvements.
Hope this helps.
Jim