Twaddle!
If you've heard Prodegies on the end of big monoblocks you would understand just how dynamic Logans can be. The main issue is you need huge power to get them to really sing in tune from top to bottom and even then, you do not get that sense of propulsion that a big cone based speaker will give you.
I owned the Ascents for some time. They needed to be biamped really, but what they did well, they did superbly. Recently listened to the Ascent i and I guess I have developed different tastes over the intervening period. I still have a soft spot for them, whereas Quads like the 989 have never really worked for me.
The problem with th smaller Logans like the Aeons and Clarity is that due to the physical size of the panel (the width), they crossover to the cone higher up in the frequency range. This does lead to some discontinuity on things like male vocals, but they can still hold you spellbound with the right material IMO.
Anyway, the only thing to do, as with any loudspeaker, is to listen for yourself.