Speaker and amp compatibility

These speakers are rated at 92db sensitivity. You should be more than fine.

The speakers handle at most 200W, and the amplifier will put out 200W before distorting heavily/reaching its limits, but you're unlikely to actually listen at levels that need 200W. The KEF 104/2 has a sensitivity of 92dB @ 2m @ 2.83V.

Assuming the Sphinx V2 has enough drive (the speakers are 4 ohms nominal, which means they may dip lower, and they may also have some difficult phase+impedance points), you'll probably only use a few dozen watts at the most unless you are sitting very far away or are trying to damage your hearing.

Thanks guys. I dont think I have ever listened to my Rogue above half.