Atmasphere is completely right about the Mini Utopias being tube friendly. I have owned Mini's for about 4 years now and have used with a variety of integrated amps, both tube and solid state. I wrote a review here on Audigon of four integrated amps I used with the Mini Utopias you may want to check out. Keep in mind that my comments were based on the Mini Utopias without any type of added subwoofer or super tweeter. I will say my battle cry for the last few years has been simpler is better.
http://forum.audiogon.com/cgi-bin/fr.pl?ramps&1229402153
With all the different amps and integrated amps I have used with these speakers, for me, tubes are the clear winner (again, see my review for explanation why). If you want to stick with solid state I also agree you should have 100 watts or higher. With tubes, in particular the Mystere ia21 integrated I'm currently using, I have found its 50 watts to be more than adequate with the vast majority of my music with only a few exceptions.
http://forum.audiogon.com/cgi-bin/fr.pl?ramps&1229402153
With all the different amps and integrated amps I have used with these speakers, for me, tubes are the clear winner (again, see my review for explanation why). If you want to stick with solid state I also agree you should have 100 watts or higher. With tubes, in particular the Mystere ia21 integrated I'm currently using, I have found its 50 watts to be more than adequate with the vast majority of my music with only a few exceptions.