I'm getting the NR kit for my conroe rig, but poeple on these forums are saying only get them if you don't plan to overclock, and instead get the HZ kit. I'm sure it's only the looser timings on the NR kit but I didn't think that madxe a difference with Intel systems. There was review of Conroes with different DDR2 timings and the performance was so close between all the timings.
http://www.bit-tech.net/hardware/2006/07/18/core_2_duo_memory_timings/7.html
Diffference between 4-4-4-12 timings and 5-5-5-15 was about two fps.