I did some more testing on the cannon energy drain bug and I verified that beams don't suffer from the same problem. There is no benefit for equipping EPS Flow consoles with beams (besides the obvious ones of recovering from Beam Overload or to quickly change power settings).
With cannons, you need 2 MK X EPS flow consoles to get most of their damage out of them, and you still benefit up to 3 consoles (although it's only a small amount for the third).
I ran 4 tests with 4 cannons at 100 energy and these were the results:
No EPS Flow: 802.455 DPS
1 EPS Flow MK X: 858.286 DPS
2 EPS Flow MK X: 906.535 DPS
3 EPS Flow MK X: 918.889 DPS (this test was actually at 99 energy due to not having enough console slots)
Based on this testing, I can say that I believe the beam results are completely accurate, and the cannon results are probably more or less accurate if you don't have an EPS flow regulator equipped. More EPS flow regulators would probably make Cannons, Dual Cannons and Turrets work better, but at the downside of giving up the ability to add a Plasma Distribution Manifold (+weapon energy) or any resist consoles.