Popcorn and a pop, I like it. I have done the pair valve which removed 90% of the popping. In the video I was aggressively downshifting to make it pop just to get a video of it. Holy Grail will be done after I modify air box and install a K&N filter.I literally made a bag of microwave popcorn and sat down to watch the videos...
That's a really sweet hollow sound you have when heard from behind.
You do seem to have popping on decel, might look into PAIR removal and Holy Grail ECU remap. I had a bit of popping on decel. and those things helped, although I never really got rid of it. Can also check for exhaust leaks...