The Klipsch will be more dynamic for Home Theater They are also more efficient than the Athena's making them a better choice for the 5660
The amp section in the 5660 will gain some headroom and be less likely to clip
when using the RF-3's One thing to keep in mind with the Klipsch is that they are very aggressive and have a forward presentation for a highly reflective room this will be exaggerated and will sound harsh and hooty
If your room has tile floor and a lot of glass I would lean toward a less aggressive speaker
Happy Listening