A:Answer I don't know which other speakers you are referring to, but these speakers are in the Reference Premier line. The reference premier is their top end speaker line, apart from the Heritage line which is their made in the USA, thousands of dollars per pair speaker line.
The Reference Premier line uses higher quality drivers and cabinet design to achieve higher highs and lower lows than their Reference or Black Synergy lines. For example, the frequency response of the RP-400M is 52-25,000 Hz. (+-3dB) and weighs 9 pounds. The larger R-51M from the Reference line has a frequency response 62-20,000 Hz. (+-3dB) and weighs 11 pounds.
You may have been comparing the RP-400M to the R-51M. The R-51M has 85 watts RMS and 340 watts peak power handling. The R-51M has greater power handling ability, but that doesn't mean that it sounds as good.