Hi cassp

While I haven't heard the Logitech speakers yet myself, judging by what everyone is saying, it seems like a good choice for a small room.

The PSR3000 like my Tyros sounds a LOT better in stereo. The single amp idea won't work well here to suit my ears by a long shot. Also, there is a built in mixer on the 3000. No real need for an external mixer.

I've heard my PSR2000 and Tyros through one speaker in mono, and it ain't pretty.

MHO,
Scott