Installed these to replace a pair of Alpine SPS-610c components. Love the bi-amped inputs on the crossovers. Out of the box they are pretty bright sounding, however can be tamed with the tweeter attenuation on the crossovers. The crossovers are very large, so keep that in mind with mounting locations. I installed mine underneath the front seats. Woofers are also very deep, had to use a 1" spacer and still remove the decorative metal piece on the magnet. Overall happy with the sound/quality. Price seems a little high for what they are however, but don't feel like they aren't worth it.
I was real skeptical about buying these since they are not made in Germany anymore. There were all kinds of negative reviews about MBQ. But I've used MBQ in 5 different vehicles since 1995 and just couldn't believe their newest speakers were the complete junk that others said they were. For me it came down to finding a 6.5" speaker and 1" tweeter capable of 150W. I didn't have much door depth to work with and I didn't want to spend more then $500 (e.g. Focal's). The QS216 met my needs and they sound excellent. I think all the negative reviews are unjustified.