The Polk's are bright and the clarity is lacking compared to the Wharfedales. I specifically have listened to them driven by and NAD integrated amps. I believe the Wharfedales are a touch warm, not neutral but sound great.

No question the Polks will be louder but not by much and louder isn't necessarily better if the sound is less than appealing. My wife and I ultimately found the Polk's to be unpleasant to listen too as we are both somewhat sensitive to brightness.

That is my bias. In all fairness, other's may feel radically different and you might be one of them.

If you can find a dealer to demo them at, it is a great way to hear different speaker performance. These two sound very different and if you hear them side by side, you will like one better than the other.