I do not think many users of FRS8 would agree with the above statement. It would have long ago been phased out of the production if it was not good as described.
I was worse than Incredulous Thomas in the beginning too.
In Voigt Pipe, it has useable output down to 50 Hz. Add a subwoofer and a supertweeter from Taket http://www.taket.jp/batpure/batpure.html, which is small enough to be positioned in front of the FRS8 as in car audio speakers, use gentle 6 dB/octave x/overs - and you have the whole thing, up to 100 kHz.
It would still be a speaker for relatively small rooms, as output of 80 mm diaphragm only goes so far and is limited in loudness/distortion in its lower end of the response. If integration with the subwoofer is done right, FRS8 based system as described above can deliver breathtaking realism at an acceptable price.
As I do not have large room available, I use Stax Lambda Pro / SRM 1 MK2 / ED-1 Diffuse Field Equalizer. It has response from around 4 Hz to above 40 kHz.
Edited by analogsurviver - 11/12/13 at 1:59pm