David, i got myself the SFC-1 (Sonic Frontiers Control) which is basicaly combination of SF-1 pre and SF-40 amp. factory stocked with El-34,(2x50wpc) however it will use 6552, KT-88, KT-90 and KT-99a. Versatility was determing factor (price too)and of course Sonic Frontiers reputation. If anyone had chance to hear this amp, i would like to hear your opinion. Thanks!