Done it 9 times now, with 20% Purple, 51% Blue, 29% Green chances, so far Ive had 1 Purple, 5 Blues and 3 Greens. Mostly you loose money compared to selling the powered consoles on the exchange, I got a (very unusually) tac console on the purple so I'm up cash wise (if you dont count buying the right doffs). It is just luck, only one of the blue consoles made it on to one of my ships, most go in the recycler.
"He tasks me. He tasks me, and I shall have him. For every doff box bought, I'll chase him round the Moons of Nibia and round the Antares Maelstrom and round Perdition's flames. For every single doff box opened, I stab at thee from hell's heart. For every single doff contributed, I spit my last breath at thee..." Khan Playing STO