I've had some large efficient floor standing speakers (and used them with 4 subs), but they were just too much for my space and I have since moved mainly to monitors - Harbeth Super HL5 Plus, P3ESR, Stirling LS3/5, and Kef Ref 1s.
It has a lot more to do with the type of presentation / sound I prefer than the size of the speaker or what's amplifying them. Which isn't to say those things don't come into play. I recently put some different amps in my system and was pleasantly surprised by the difference they made.
I recently picked up a pair of Thiel CS 2.3 floor standing speakers and have been really enjoying those. Their smaller size and design works really well in my room.
The best system I've heard so far had speakers 8 feet tall. Part of the fun of this hobby is trying different things and keeping an open mind and not deciding it has to be this vs. that.
In regards to the derailment of the thread, all I can say is that when a manufacturer or dealer comes into a thread and presents facts about a situation they've been questioned about or educational information and deals with others in a respectful and professional manner, my respect for them grows. If they show up denigrating members and putting down their systems and threating legal action, well... I'll steer clear and spend my earnings elsewhere.