Panasonic sa-xr45 sa-xr70 is the newer improved

I have an XR10. It's quite smooth. I think the newer ones are a little harsh.

I have an SA-XR25. These HT receivers have to be run in for a long time to have them respond well. They're harsh fresh from the box. Setting them up with all outputs terminated to a speaker of some type and leaving the radio on low volume for two weeks continuously should sweeten up your panny...
That's a tough thing to do because we all want to take it right out of the box and put it through the paces. But have patience. You will be rewarded.

I have an Panny SA-XR50. Compared to my Jolida 1501 hybrid tube/MOSFET amp, the Panny does have a bit of an edge to it. In all other respects, imaging, response, dynamics etc., the Panny is an awesome amp for the money. The Panny is really my back-up amp now.