i was thinking of getting the callisto at one stage given its rave reviews in germany and australia. it is apparently better than the tabu integrated amp with more power and control. if you don't need the phono stage,consider the smaller and cheaper callisto 2100( 100 watts, pure class A, dual mono integrated amp). go visit the www.audioconnection.com.au web site. i think they offer competitive prices for the gryphon gear, which they distribute.
good luck!