I can tell you that a couple of months ago I bought a used pair of Coincident Triumph Extreme MK II monitors. They are 94 dB efficient, and designed to be driven by low powered SETs, like the Coincident Franks, 300b, 8WPC I believe. Now, I am currently driving these with 500 wpc mono blocks, because that is what I have. I am extremely impressed with these monitors. They are extremely coherent, very articulate, fast, and they have great timbral accuracy. Of all the speakers I have ever owned, these please me the most. They are just great, great, speakers. I'm using them in a 15.5' x 19' x 8 ' room, and they play effortlessly at fairly loud levels.