I agree with audiokinesis. Although a speaker's sensitivity should be considered when matching them to an amplifier, it would be wrong to use the sensitivity rating as an indicator of quality. Many speaker designers opt to trade high sensitivity for deeper base production, especially in smaller enclosures. Remember also that generally a tube-powered amplifier will seem more powerful and play louder than a solid state amplifier of the same or similar power rating.
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.