Ubu, I don't want to frighten you, but consider that, a part catrdriges, loudspeakers are the most "wearable" component of the system. The foam suspension of the speakers, tweeters and woofers, tend to age, even w/o using them. So be very careful about used loudspeakers and check how the foam's suspension appears, otherwise you'd have to replace the components, and that it could cost you more then 30 euros, expecially if that particular component is discontinued from the factory, in that case you have to replace it on both speakers. I personally wouldn't buy used louspeakers without checking them personally, but yes, 30 euros...is tempting.