Roadkill Fast Rings or Equivalent

[Cutaway]

https://stingerelectronics.com/colle...ill-fast-rings
Just curious if anybody uses these or an equivalent?
What is the overall opinions of using these? I am in the middle of installing them, drivers side doors. But I really don't hear a difference and now debating if I should continue to the passenger side.

Any experience or even unfounded opinions are welcomed

[lithium]

The foam ring is not dense enough to block sound so its ineffective at directing sound out of the door trim opening. The typically recommendation is building the baffle out to almost meet the door trim and using weatherstripping as a gasket between the two. Also, the foam ring that goes inside the door is too thin and too small to absorb much of anything. Thickness of the foam is inversely proportional to the frequency absorbed, for a mid woofer in a door its ineffective at the frequency range this driver reproduces.