I'm still not clear on what you mean by drone. A drone is a steady monotone sound,which would be like when you are cruising steady down the hiway not when accelerating or decelerating. Do these have what you are calling a drone?
Click:
Well,never mind. I guess you can't tell. I had the window open and was rolling at 50-55 except when I got it on. But,those are Flowmaster 2 chambers and I never felt they had a drone at cruising speeds. At least not what I consider a drone. Certainly nothing bothersome...again,at least to me. It may have more to do with where the mufflers are located than which muffler you use. Mine are under the bed,2 1/4" all the way back to behind the wheels out the sides,I have full length headers,and no crossover.