I am a fan of the low power / high efficiency pairing. I also feel that most higher efficiency speakers sound like live music and can be more dynamic. I think they often sound better at lower volumes. Just went from a pair of 40 watt Push Pull amps to a 300b and it's plenty of power for my space and listening habits.
What is your take on high efficient speakers vs. low efficient speakers?
Consider both designs are done right and your other equipment is well matched with the speakers. Do you have any preference when it comes to sound quality? Is it matter of economic decision when it comes to price? - power amps can become very expensive when power goes up, on the other hand large, efficient speakers are expensive as well. Is your decision based on room size? I'd love to hear from you on the subject.