Bingo. The K100 has such an improved speaker over the 50 that it almost makes the 50 unnecessary. I felt like whatever was in the Nextone stage sounded very similar to the K50. I wonder if the Nextone Artist fares better, but given it's price and the way I felt about the Stage... I'd be hard to convince that this was the way to go over the Katana 100 or any of the tube amps that are within that hotly-contested price range.