This is all about listening preferences. Note that I am careful to say that the Pipettes are intended for use in typical living room/desktop/nearfield/non-critical listening environments. For example, I use a pair with a StereomourII amp (about 4 watts) in my 15'x20'x11' studio office. It is a great setup for listening while working. With 4 watts per channel we are looking at maybe 91dB peaks. Average listening levels are typically in the 82dB range so there is some headroom. Without a subwoofer the speakers start to roll off around 70Hz. So there is still reasonable output maybe half an octave lower than that, say around 55Hz. A subwoofer is a nice addition but not an absolute necessity.
Now if I need to impress audiophiles with excess, maybe play some techno so I can feel it in my gut, or play that killer Nojima Plays Liszt album we reissued on tape at live performance levels - I will switch to my 95dB speakers and 35W amps. Then we can hit clean 110dB peaks. I can only crank that puppy to the max once in a while and not for too long. My ears will be ringing afterwards and anyone else around will ask me to turn the damned music down. Luckily the neighbors are almost never in their office or they would certainly come over and complain when I crank it. And of course this is a setup that costs maybe three or four times as much as the Pipette/Stereomour II setup and takes up about four times as much space.