I bought this cabinet two months ago and the first thing he is careful to say it! clearly, if your speakers are less than 300 w rms, you will not hear them!
rather compact compared to his (sorry, the sound pressure!) just leave it, this box amplified average power (600w rms qd same) you will be satisfied for your private parties, but just be a little over 100 individuals or in large rooms.
I use it with a pair of speakers mackie srm 450 (400w rms) and j'obtient sound quite extraordinary. open to all frequencies and not aggressive either.
it's really good material, can be a bit expensive against the race condition, but also much more efficient.