Graco or 100 Straight Dead Mule recoil reducer in an H&R Handi-rifle?

Has anyone ever tried one of those recoil reducers that fit in the stock bolt hole on a Handi-rifle?

The .444's and .45-70's in particular have quite a stout kick and I was casting about for something to dampen it a bit. I checked my .444 and the stock bolt hole is the standard nominal 7/8" in diameter and about 8" deep. The reducers I've seen are made for a 7/8" hole and are only about 4" long, so they'll fit OK.

Here's the Graco:

http://www.midwayusa.com/product/678973/graco-breako-mercury-recoil-reducer-standard-7-8-x-4-14-oz?cm_vc=1976BrandPopProd

And the 100 Straight:

http://www.midwayusa.com/product/138587/100-straight-dead-mule-recoil-reducer-fits-stock-bolt-hole-7-8-diameter-x-4-1-4-long

interesting...

I'm also interested to know if anyone has tried these. I was thinking about trying one out in a shotgun for my wife.

Got a buddy that has a 12 gauge slug gun h&r. Has one in it. He swears you can tell a difference when you take it out.