Quick show of hands, everyone here who conducted their last blind listening test with a PANEL of TRAINED listeners, say aye. Congratulations if your every audio purchase gets judged by your panel. See the link I posted above:
"If you want to take the variable of the listener out of the equation, then your listener panel needs training."
When I buy new gear I get a 30-60 day return period. I drop it in the rack, let it break in (I know, the horror) for a few weeks and then take it out. If I don’t miss it, refund. If I can’t live without it "grinrictus" sets in and I buy it.