: thanks. I wish I knew whether a non-drone was louder than stock. To me, any noise that goes on and on and on (as in driving at 75 for an hour) is a drone. Saying it does not drone makes no sense to me.
Short Answer - If you are looking for an aftermarket exhaust that has a totally stock sound/loudness on the freeway, I think you should just stick with the stock muffler.
Long Answer that may better impact your decision - I have a 2005 Elise since 2006 with a stock exhaust. Then recently this past June got the SonicFury DE. With normal around town driving/engine load, it's going to be LOUDER in general. What I found is when you throttle the engine even a bit (i.e. normal acceleration around town, between 1k and 3.7k rpm, whether babying the throttle or not) the volume of air going through your exhaust it going to produce a deep throaty sound with the SonicFury. But once you hit your driving speed, with no load to the engine (i.e. a steady 3k rpm on a perfectly flat road), its nice and quite. However, this isn't really achievable for a long duration...or at least where I live as I have lots of hills, curvy roads, etc. With these factors, I'm constantly letting off the throttle or giving it a tad bit throttle to maintain lets say a perfect 25 mph around my house. The tad bit of more throttle will create a throaty louder than stock exhaust noise, as expected. Now there is a sweet spot where about 3.7k to 5k of gentle throttle, it's not that loud. I can hear my engine noise more than the exhaust.
So can see where I'm going??? This also applies to freeway driving. If your on a flat part of the freeway where you can maintain lets say 75 mph without needed to play with the throttle ever so slightly, it's quiet and you'll love it. But if your freeways are hilly and you need to throttle it to maintain your speedy (e.g. 75 mph) you'll hear the throaty exhaust note. The throaty exhaust sound going on, off, on, off, is dependent on the amount of throttle you need to give your car to maintain a certain speed. An exhaust with drone, per say, is never quiet. If you're driving 75 mph on a perfectly flat part of a freeway and maintaining the same rpm/steady throttle, the muffler will make a constant somewhat loud throaty sound which eventually drives people crazy.
Couple more items...I put a BOE Rev 400 Supercharger in the car this past August. My guess is that with more airflow through the exhaust now, it's going to make a slightly louder throaty sound as I give throttle. And last week, I drive the Elise on a business trip from the San Francisco Bay Area to Sacramento (120 mile drive). On the flat parts of Interstate 80 & 50, the level of exhaust noise wasn't bad at all when I needed to ever so slightly accelerate.
Hopefully the info I provided gives you a better idea on what to expect.