I have the 2310 but I would not expect much more from it with audio than the 1910. It does have a few more options and a better video scaler but for audio no big difference other than slightly more power which won't change anything in terms of sound quality with the 22's. These are good receivers, and you are not driving real hard to drive speakers with it, so I would not worry at all. To really go up in quality in the receiver you would have to spend $2000 or so to get the high end made in Japan Denons/Onkyos/Pioneers/Marantz etc.
You are correct about the sub, the amp does not send "power" to the sub, it just sends a signal which is then driven by the amp in the sub itself.
