The Argent Rooms Lens have a damped control apperture thru the bottom vent for bass control and pressure relief.
So basically a resonator.
My suggested placement after 20 years of use is 6 feet outside the edge of either speaker
Diffusion at this spot would aid in controlling first reflections.
and 1 dead center of my mechanically grounded audio system..including the Room Lenses.
Also usually a very good spot for diffusion. May provide limited bass control.
Tom, this is not meant to put down the product, but to suggest how it is likely working in your system. I expect their benefit is more from diffusion than bass control. Room measurement would show that in a few minutes, however, not placing them at max room nodes limits what they can do in the bass. I would not put these on the silly scale. I doubt they meet all their claims, but could certainly see them being useful.