Has anyone tried using this filter? It has been updated for Avisynth 2.51. I used the default settings on a sample, and it seemed to look as good and work at the same speed as anything else that is used here.

http://members.tripod.co.jp/kiraru2002/#dnr2

dynamic noise reduction (MMX) by Steven Don and Avery Lee

DNR2( threshY_hi, threshY_lo, threshU_hi, threshU_lo, threshV_hi, threshV_lo, type )