Ive had these for a while now and am very happy indeed. they are a really well rounded speaker and they fill the room with music. Ive looked at the sensitivity and they list these at 89db and 6 ohms nominal. Does this mean they are not easy to drive? im using a croft power, but PMC suggest amps up to 400wpc. Theyre easily handling the croft power and I feel could use more power and be better still, especially at higher volumes.. I dont know how powerful the croft are, and glen croft says he can improve them further, im wondering whether there would be any gain from a more powerful power amp, though I would probably ask Glen to upgrade the croft, rather than change amp...its a croft s4?? Ithink