You are only looking at on axis frequency response, off axis is just as important in most cases except in near field listening which most people don't do! Also, you are mistaking a larger frequency range as better which isn't necessarily the case "what SPL can it maintain this linearity at?" is another good question since many speakers with a lower end can't play those low frequencies loudly enough to be useful.
You really need to stop focusing on one specification of the speaker as it doesn't even tell close to the whole story!
Yeah, like I did say, specs & numbers don't tell the whole story: "I am aware that specs & numbers don't tell the whole story. There are other factors like actual sound & aesthetics."
When people buy speakers, obviously most of them cannot audition every single speaker. They probably want a starting point. So most people will first look at the specs. That's their first impression. If the given specs don't even look impressive, people are probably not going to even audition the speakers. If the frequency response +/- 3dB is not important at all and nobody cares, I guess there's no point for speaker companies to advertise it, is there? I mean is there a more important spec about a speaker? Sensitivity? Most companies don't even tell you their off-axis response, so it's very difficult to compare.
So I hope this doesn't offend people with speakers that don't have great overall specs. It's okay. They are just numbers. That's all I have to compare them with. It's just a starting point.
I'm just stating the obvious fact about the MB Quart S-One. Without having the opportunity to audtion one, it's my first impression of it.
Has anyone actually listened to a pair?