The speaker to look at in that range would be the Focus HD or even more so, the new Focus SE (can be had on Audiogon/demo market for a bit less than retail). I've owned the 20/20s, HDs and SE and am currently solid on keeping the SEs for many years to come. They handle any type of music I throw at them with ease and a transparency and naturalness that is very hard to achieve and usually much more expensive, with many other speakers. They will easily take up residence and do well in your 18x20 room. The Whispers would also do well in that room; I've heard them in rooms that size and larger. The way the Whispers render sound in much more independent of the room itself (see video from Legacy on this as well...); they would do well in your room. It all comes down to price-fit and what types of music you listen to. In either case, they are extremely easy to place and tune for great listening in your room.