I had the Berk with HFC's and there wasn't a hint of what I would consider drone. Sure it was louder than stock and there were a few RPM's where if you let it hang there it could get "droney" (<-new word
) I'm sure it would be even quieter without the HFC's. It's a good sound and will keep you sane on the highway.
I loved my Berk but now that I am TT I felt that I needed the bigger exhaust. That's why I went with the FI 3" non resonated. Now I know that will be droney.