I think I have tracked the problem down to it being that my cables are responsible. I've done tests involving all types of cables including insulated and covered with the foam. Also I have performed these tests between nuclear reactors to an MFSU. I at first thought this was a problem with the Reactor so I tested with other types of generators with no success. The first 2 pictures below showing the Nuclear Reactors internal power stuff and the second being 1 of the few wire tests attempts to get power to the MFSU. I will also note that they were attempting to send power onto one of the 5 "Input" faces, and not the one "Output" face.
My second test was entirely skipping the generator/reactor stage and jumping straight to the MFSU and sending power out along it to other sources. In this instance to send the power into a connected Luminator. So I grabbed a few stacks of redstone and tossed it into it to give it some power. With the cable attached to the "Output" face as you can see. The Luminator failed to light up even though there was plenty of EU to power it in the MFSU The pictures below showcase these things.