The only way to kill the drone is with a UQ in the tailpipe but you have to remember the tailpipe must be vented outside the body or box to eliminate resonation back into the cab.I went with the 40944 so far without the ultraquiet. I'm running the Cajun set up with reso Bpipes an love he sound. Get a lot of compliments on it.
Only thing that really drives me a bit crazy is between 16-1850 rpm or right around the drone can get annoying. If that kinda thing doesn't bug you it's the way to go.
I tried about 20-30 different setups now and to eliminate drone with a 40944 it must exit.
Even with a UQ in a full tail if it does not exit outside the body line you will have drone.