The biggest disadvantage of docks is that you can't separate the speakers. Speakers are best placed in an equilateral triangle with the listener to achieve the best soundstage and imaging
In other words, docks are what you choose (a) for convenience of plugging in an iPhone and (b) for when you don't have room to separate speakers. Not because they will be better sounding.
That being said, user listening tastes are always a factor. You might like the sound of one of the docks better.
As for driver composition, there are expensive speakers made with paper drivers. The composition alone won't tell you which are better.