Well I have to tip my hat to Bowers group. Tom (the owner) made a personal visit to my house, (granted I live 15 minutes away from them) he brought out both their dreadnought and vers 375 just so I could give them a try.
I wish I would have had more ammo loaded up for my 338 but I fired rounds thru both and felt like the dreadnought was quieter which stands to reason since it's longer and per Tom has just the needed length to have another stack of baffles in it.
I don't have any experience with any other suppressor for this size cartridge but I do own a thunderbeast ultra nine that I shoot on my 300, overall both suppressors tamed my 10.5 pound 338 terminator down to a very manageable shooting experience.