I used one on a Winchester 70 Classic 25-06 that didn't group like I've come to expect.
Even after removing the hot glue and bedding it properly, tried free floating the barrel and pressure in the fore-end, multiple bullets, weights and speeds.
The de-res doughnut did help but I'd lost interest in the rifle by then and sold it to a buddy who immediately removed the de-res.

"Camping places fix themselves in your mind as if you had spent long periods of your life in them.
You will remember a curve of your wagon track in the grass of the plain like the features of a friend."
Isak Dinesen