They're not much better than Rakata, which you can get for daily comms.
I think the best think to do, is make an AskMrRobot profile with your current gear, then try out various Black Hole options and see which one does the biggest benefit to your stats.
Unless you already have a Columi offhand, the BH offhand is often the biggest increase.
you do have a point on the quality. my answer was bent in favor of rapid improvement. A brand new 50 after the 25 comms get handed out needs one HM flash point to the bh implant/ear vs 120 daily comms starting from zero.