I see where you are at with the Yamaha. The stereo audio aspect actually is very useful for many things, including just listening to your iphone or cd player in stereo. My DA5 is half way decent with the stereo to mono adaptor plug but stereo would be cool. The bass capability is also very cool, not to mention the recording interface. I have a couple separate recording interfaces. I like the idea of being able to play along to jam tracks. That is very cool. I am using a JamMan looper which is fun and useful, but stereo jam tracks sound super fun. The fact that the interface is simple is also interesting.

It looks like it may make a totally awesome multipurpose device. That and a laptop could make an awesome mobile mini unit for having a lot of fun.