If you happen to like that particular Carver, go for it. If you are keen on transparency/accuracy, the MCA 325 would be my choice, I would bet you 5 to 1 in a properly set up blind test you cannot tell it apart from the STR or any amps that are design to be transparent. If you it sounds bore in your room with those Focals, try EQ to suit your taste.
For price, you can't beat the QSC DCA and Crown XLS. Verdinut said the fan in the DCA was quiet, but I suspect if you sit close enough, listening at low level in a very quiet room, you may hear it.
Impedance dip or not, it depends mostly on your sitting distance and spl you listen to. As I mentioned, I am quite happy with my 5 watt amp diving the 1028 Be, that has similar power requirement to the Kanta's.