I can do 50-80 mph down the highway and not hear any drone at all. It's a mellow tone but very deep sounding, kinda sounds like an older big block muscle car. If it gets to around 2500-2700 rpm it has a little bit of drone but then its gone right away as you keep accelerating. It's just in the one spot in the rpm range but even then, it's not horrible.
Really like the sound of this muffler. It's exactly what I was looking for because I really don't care for the super loud systems, or cackling, popping sounds on decel etc... I've only had it installed for about a month but I can't wait to ditch the cats and install the longtubes with it. Should have a pretty good bark at WOT.
Here are some pics that I took of it when I first got it. If you're familiar with 4th Gen fbody exhaust systems you might be familiar with the SLP "2 on the left" system. This muffler is almost exactly like that muffler and sounds very similar which is the sound I was going for. You can search "SLP 2 on the left" on youtube for some sound clips. Notice how free flowing the muffler is.
Mike