To some point, the db reduction is important. Some cans do suppress better than others. The simple answer (in general), is the larger the can, the more it will suppress. If you put a large 338 can on a 223 or 308 rifle, it will be much quieter than a normal 223 or 308 can will be on the same rifle. It's simple physics. I run an old Shark Tiger Shark 300 Win Mag suppressor. It is a HUGE can, and has a large internal volume. It is quieter than other smaller cans I have shot side by side. But I expected that. And the smaller cans shot on a 308 will naturally be louder. The baffle design inside also has a large roll. But the main thing would be comparing the size of each can to the next, not just the db reading. A 7"-9" can will be quieter than a 6" can will be. It's simple physics. So, without the sizes of each suppressor they used, it's not a helpful or apples to apples test, as they say.