It's getting all Audiogon in here LOL.
Two of my buddies are big time audiofiles and they get together and swap speakers around and A/B speakers and cables, etc. Kind of fun to here the difference when I got invited to sit in with them. I love the $600 Maple Shade 3 inch thick maple subwoofer stands and huge brass isolation mounts for the huge 18 inch JBL subs my buddy has LOL
Most of the time that I've done direct shootouts where there has been a difference, it's still really subject stuff. I did a shootout of Traynor heads and Ampeg 810 cabs with chillerthanmost, my YBA-2 and modern 810 and his YBA-3 and flatback 810. Both heads through the same cabs, both cabs with the same heads. There were differences, we measured SPL levels, listened at different settings, but I wouldn't say it was anywhere close to night and day. That's my interpretation, if you were down to trying to squeeze 2 or 3 dB out of a cab or being able to get one more extreme amp setting out of either one, maybe it would be a huge difference to someone. Some things are just apples and oranges too. That's how I view the Dually vs my 810. Head to head with another ported 215 you can compare subtleties, but against completely different cabs it's just...different.