Has anyone tried these products?

Agreed with @baylinor . You want more of an acoustic diffusion rather than just absorption. A lot of people get these panels for big noisy rooms or churches or attic Studios or things like that. There are several purveyors of good two feet by 4 ft acoustic panels out there. You can also try this:

https://www.costco.com/artika-sonolok-sound-absorbing-slatted-panel-kit.product.4000320081.html

I could not find any technical information at the Audimute website.  

I haven’t emailed them yet to get any information and being only 1.5” thick, I’m guessing the absorption is limited. I also agree with @baylinor , that there’s probably no way they can absorb 95% of the sound.

I’ll try to send them an email and see what they say.

@simao 

Thanks for the link,

but I wonder how effective they would be at only .38” thick?

@curiousjim  that's the thickness of the backing. The slats themselves are an inch thick.