I prefer Sidney Cordnerman's opinion of Class A amplifiers. "The efficiency of Class A is really poor. They're generating a fantastic amount of heat when they're not amplifying a signal. I saw no advantage in considering Class A. If you properly bias Class B or Class AB, you don't have crossover distortion, so you can do a good job, and have high efficiency at the same time."
http://www.audioholics.com/audio-amp...lifier-classes