I have a C500 driving a set of Duevel Bella-Lunas, and a 102/Capri pair driving a set of Duevel Venus. I love the sound of the "modern" Rowland amps, it is so smooth and effortless to my ears. These amps just seem to idle their way through the music and never get rattled, even the tiny 102. I found break-in pretty extended, about 300hrs before the amps settled down. The C500 ran pretty warm for the first week, but then the temp seriously dropped. I don't understand how but now my C500 is cold to the touch, and sounds great too.