I have had zero issues with doing this. I will also add that one of these is in the same small enclosure that I have SSR's and high voltage going to heaters for a test apparatus and have still not had any issues. Reading the TB that AlexUT posted, I don't see why you could not loop the wires through a ferrite bead or donut/choke to reduce any minor EMI. It would look like crap but you could also separate all the strands then twist them back together with a choke. I have those extenders in 3 pieces of test equipment that we built. We are using them to write a continuous log during tests. Mind you, I am a chemist, not an electrical engineer, all those ideas to reduce EMI work awesome in my mind, but in reality may differ.