The B&W DM600 series have been in production and popular for a number of years, as good all round and respectably priced speakers. B&W started out in Worthing in 1965 and have grown to be a highly successful and global firm.
These B&W DM602 S2 (Series 2), should be a good buy. The aluminium tweeter and Kevlar driver, not only provide great sound, but make it robust and reliable, thus a fairly safe buy second hand. Their a little large at nearly 0.5m tall, but have good bass response and are sensitive enough to partner a modest amp. The front facing port, allows them to be situated close to the back wall of a small room and also ideal as a near field studio monitor.
Also check out this funky video tour of the B&W factory:-