At those prices, they better be the best, not just 'good'. SQ comps require a flat response from 20Hz-20kHz and multiple processors to achieve those results. You should theoretically be able to take just about any decent speaker, put processing on it and achieve a really flat result.
I've heard 'flat' EQ'd systems for home audio, none for car, but if they are anything alike (I imagine they are) then there is virtually no low-end and that sounds 'fake' to me. Like what a old style phonograph sounds like. Midrange, tinny and irritating with no smoothness.
I tried a home audio experiment. I had a friend who could sing come into my home. I played an acoustic recording of a vocal only after setting my home system to flat frequency response using my EQ. I wanted to achieve vocal accuracy in my home. I played the piece of music, then I had my friend sing. I quickly decided that my system 'flat' didn't sound real at all. It was phony. I tried multiple tracks and found that on multiple tracks of varying depth of bass on vocals still lacked any true realism.
Then I started adjusting the EQ and played tracks, having my friend sing every once in a while. After a couple of hours I got my system to sound real close to an actual singer on most tracks. So, a 'flat' 20Hz-20KHz for me doesn't sound 'real' and 'real' is what I strive for.
Another critical element in speaker listening I search for is 'image'. Does it sound like I'm wearing headphones? Do I hear not just right to left, but like there is a depth in front of me that stretches out far beyond the speakers? I found that you can't EQ that into a set of speakers. They either have depth of image or they don't. You can play around with a device like an HRTF processor to try and force a more spatial effect but my speakers don't need it.
I am very critical on my speaker selection and evaluation. Here are the items I judge on my sheet of paper:
Tonality - Do instruments and sounds seem 'real'. (Different acoustic environments will change some characteristics of the sound, but not some specific ones you can still listen for.)
Image - When playing binaural recordings or playing music that use a lot of echos/ambience, does the sound stretch out? (And don't get fooled by the ambience/echos of the room you're listening in.)
Dynamics - When a drum hits, is there a sharp impact? When an orchestra builds to a climatic crescendo, does it sound like it's increasing in volume? Can you sense it's getting louder? (Some speakers sound dull and lifeless, with what seems like a equal-loud output from soft sounds to loud ones. If you want an extreme example, listen to electro-static speakers from years ago.)
Overtone/resonance - All speakers seem to have this, except the most expensive I've heard. On lower mid-range sounds, listen for a lingering ring on top of the sound that is not part of the actual music and is not part of your acoustic environment, but coming from the speaker itself. Virtually all speakers have this in one degree or another. Some that manage to minimize it, seem to do so at the cost of imaging. The rare speaker that has deep image and no additional resonance is usually VERY expensive. Yet most 'expensive' speakers still have this problem. The best speakers I ever heard were a set of Snell Acoustics THX cinema reference speakers. At the time they were being sold, they cost $30,000 for the whole setup.
Sibilance vs air - I've noticed that when you try to minimize sibilance in sounds, you lose some of the 'air' in the soundstage. And when you try to open up the soundstage to improve imaging, you increase sibilance on vocals and over accentuate the sound of 'clicks' 'ticks' cymbals and chimes. This can be improved with an EQ and is not something you are doomed with when buying a set of speakers. Some people refer to these kinds of speakers/tweeters as 'bright'. Most tweeters can still be attenuated to improve the realism. There are metal tweeters that have no hope of sounding realistic. I absolutely hate Boston Acoustics tweeters. They sound metallic and phony to me. Some people like Boston Acoustics, and I don't want to start arguments or offend, but they are some of the worst tweeters on decently priced speakers I've ever heard. I can hear them immediately upon entering a car audio shop. They have a signature sound that is hard to miss and I guess you either love it or hate it.
Those are pretty much the big 5 for me. Opinions on speakers are going to vary. The best thing to do is listen to a set of speakers with your own ears, reject anyone else's opinion, and apply those 5 critical listening examples whenever you evaluate. You will end up with a good set of speakers just for YOU.