To be honest i wouldnt...
my reasons to run one apollo would be inefficient as youd only need 250 watts max
run two apollos in eco mode maybe... but i still wouldnt these arent the most stable types of psu's
at this stage this is obviously speculative and until ive use an apollo for a while couldnt really be 100% sure.
Id err on the side of caution look at hp or dell server psus and a breakout board (basically and adapter for 6 pin pcie leads) some refurbed bargains around and theyre very efficient, stable and built to be longterm work horses.