Shunyata says to go with the NR. The sale is still on. I spoke with a great guy at Shunyata very recently and he recommended the NR over the EF for any streamer. Customer feedback is 50/50 with the NR combined with tubed equipment. Shunyata also says it's ideal to stay within the same level throughout your system. My understanding is that you can substitute Alpha with Anaconda within a system. I hope that helps in deciding whether to go Alpha or Sigma. Enjoy your Innuos ZENith MK3!